If there ever is an NPC or in some cases, NPC's from other mods like The Train, Diamond City Expansion, or any mod that adds NPC's or followers, that you want to turn into cute Anime characters, there is a relatively easy way! All you need is xedit, or FO4edit, in this case.

When I was starting out, I used petrifiedichor's tutorial here : https://forums.nexusmods.com/index.php?/topic/7616648-nanakochan-npc-replacer/page-8

But as he said, it's a bit of a lengthy process that is also prone to human error, I managed to speed up the process by a little, but I'll give you a basic run down because it's a very good tutorial.

1. Open Xedit.

2. Select the mod you want to use.

3. In the NPC section of the mod, pick any actors that use the "Human Race", you can put RNAM or Race in the "Filter by name" box at the top.

4. Make sure every NPC you have selected is an actual human character, It's not the end of the world if you mess up and a Ghoul NPC slips in there (you can even edit and turn those into anime characters if you like) but if it's something like a Feral or a Deathclaw, you're screwed.

5. Right click and select "Copy as override into..."

6. Scroll down to the bottom of your load order and select a new .esp file, you can also just copy as override as into the mod you want to edit, but I don't recommend that because if you mess up, you have to reinstall the mod.

7. Select and right click your new plugin, and click on "Add Masters"

8. Select your AnimeRace_Nanako.esp also make sure the anime mod is on top of the mod you are editing, adding masters basically means you can use the master mod's assets and stuff, in this case, we want to use the Anime mods Anime assets.

9.Now select all the NPC's in the mod you want to edit, and scroll up to the Anime Race ESP.

10. Go to the Anime ESP's NPC section, this shows all the presets, Nana 1 has the cute eyes and slightly tanner skin, Nana 2 has neutral eyes, and Nana 3 has the cool, annoyed eyes.

11. Choose the preset you want, ctrl select it, and right click, select the top option "Compare Selected" the option also shows the amount of NPC's you have currently selected, anything over 500 NPC's means you are going to do a lot of waiting.

12. Your Anime race preset should be the first one on your new row.

13. Compare selected will now pile all the NPC's you have selected into a nice row, here comes the tricky parts.

14. Head over to ACBS and look for the value FEMALE, which is under Flags(sorted), your Anime preset should also say FEMALE, right click on FEMALE and select "Copy to selected records" a box should pop up showing all the selected NPC's, make sure all of them have been selected and click OK.

15. Head over to RNAM and do the same.

16. Scroll down to WNAM - Skin, you'll notice your anime preset doesn't have this, or is empty, don't worry.

17. Right click on any the value that says "Skin Naked" or "Dirty".

17B. There are two ways of going about this, you can double click on the WNAM - Skin value and a drop down menu will show up, all you have to do is type in nanaNaked [ARMO:XX001F00] and select it, the two X's are the two numbers next to your Anime Race .esp, in my case, it was 11, but yours may vary, depending on your load order. Or you can just copy and paste that value above and replace the two X's with your two numbers, simply right click, select edit, and paste it in.

18. You have edited the skin, but only for one NPC, now you have to select that value you just edited and right click and select Copy to selected records.

19. MAKE SURE YOU DO NOT CHECK YOUR FIRST ANIME PRESET, IF YOUR ANIME PRESET IS AT THE TOP, YOU MUST UNCHECK THE BOX NEXT TO IT.

20. Or don't it really doesn't matter what you do, as long as you don't save the actual Anime Race ESP when you save, but just be sure.

21. Slide down to FTST - Head Texture, and do the same thing with the WNAM - Skin, right click on a value, only this time, type in nana_head_color [TXST:xx001F01] make sure to replace the X's.

22. Once again, Copy to selected records, make sure not to have your Anime Preset selected, that row needs to have an empty WNAM slot.

23. Here is the most tedious part, slide up to Head Parts (Sorted), you'll see a ton of values with names like face and hair and beard, those are the vanilla headparts, and those need to go.

24. But first take a look at your Nanako anime preset in the Head Parts section, notice how it has all the parts labeled Nanako. those are the only ones we need right now.

25. You should right click on each piece, and select "Copy to selected records" for each and every NPC.

26. But it is tedious, right? if you have to edit a lot of NPC's or your computer is slow, simply right click on the nanako headpart, and select "Copy Multiple to selected records"

27. A box will pop up with all these check boxes, deselect all of them one by one (I don't know why we can't select and deselect multiple boxes) EXCEPT HEAD PARTS.

28. Then just apply it to every NPC.

29. Now here's the thing, PetrifiedIchors tutorial has you selecting every Vanilla NPC headpart EXCEPT their hair, and deleting it, everything that isn't labeled as hair needs to be removed, now as he said, this is not only boring and tedious, this is also prone to human error, especially if you are editing a lot of NPC's.
So I've come up with a way to make the process a bit faster, only by just a bit, but it is faster.

30. Scroll up back to your Anime Race .esp, DESELECT your Anime preset by ctrl clicking, and scroll back down to the mod you are editing, scroll down to NPC's and right click on the first one and select "Compare Selected"

31. Now scroll back down to Head Parts (Sorted) right click on the box directly next to it, and select "Remove from selected records" this should completely delete the vanilla head parts and make the Head Parts section completely greyed out.

32. Now RE-SELECT your anime preset and right click and compare selected once again.

33. All the head parts should now only be filled with Nanako head parts.

34. Repeat or go through steps 24 to 28.

35. Right! you have now replaced all the head parts! done, right? well, not exactly, while you can just continue, you'll have a lot of characters with the same face in your game, so, to prevent severe Same Face Syndrome, you'll have to double click on either the Hair parts, or Eye parts, for each NPC and change them, one by one, this is a bit tedious, but it's way better and not prone to human error, plus, you get to choose what eye color each NPC has and what hairstyle they use, just make sure they all have Nanako in their name.

36. Almost done! all you have to do now is scroll to the bottom where you will see values like MSDK, MSDV, Face Tinting Layers (Sorted) and Face Morphs (Sorted), these are basically the vanilla face sliders and valuables, which we don't need since all Anime characters have perfect face shapes, So just select the topmost row that's green and right click and "Remove from selected records" the values should be all greyed out after doing this.

37. Now just scroll down to FMIN, which is just another face morph related thing and find any value in this row and delete it! which will make it completely greyed out!

38. Now all you have to do is save, and congrats! You're done!

Now simply enable the ESP, head into your game and check it out! if something isn't right, or you want to change an actor's hair or eye color, just head back into xedit and change it!

This looks like a really long Tutorial, but once you get the hang of it, it takes about less than ten minutes? depending on the size of the mod you are editing of course, the longest and most tedious part would be finding the right NPC's to edit, and making sure they're not Synths or something.