A full guide/mod list for New Vegas on Valve's Steam Deck.

Disclaimer: Your game and all your mod files MUST be on the internal SSD. You can install the game on the SD card. Just leave mo2's paths default. have designed the guide/mod list to take up as little space as possible, so even if you have a 64gb model, you should be fine.

Section 1: Requirements

1. A clean install of FNV. Make sure you delete your previous game folder to remove any leftover mod files. This guide will assume you have the game on steam, but it should work with GOG as well.

2. Proton tricks installed from the discover store.

3. The latest release of rockerbacon's MO2 Installer from Here.

4. Roughly 15 GB of free space on your SSD (if you delete the downloads).

5. 5-15 hours of time.

Section 1.5: Space tips
If you are hurting for space, then these tips will help you manage.
1. Change Firefox's download location.

Helpful for if you are downloading bigger mods. To do this go to Firefox's settings, search "downloads" and click browse under the "Save files to" option, then navigate to a folder on an external drive.

Section 2: Installing MO2
Once you have downloaded the installer, extract the contents, then run "install.sh".
(You may have make the file executable)

Then go though the installation process, keeping all paths default.
When prompted about prefixes, just click no and then All done lets continue.
Once MO2 installs, open the game thought the newly created desktop shortcut.

Section 2.1: MO2 Linux "Quirks"
There are a few quirks to MO2 on Linux.
Firstly, you cannot download a mod using the Mod Manager button.
Secondly, in desktop mode, if you leave the window idle for too long, MO2 may crash.
Thirdly, you may have to hold down the steam button to use the mouse, and the keyboard may not work.
LOOT may also freeze mo2 in desktop mode.

Section 3: Utilities
First, close MO2 then install xNVSE from here. (or the nexus page)
Then manually download the following mods:
JIP LN NVSE Plugin + its ini
JohnnyGuitar NVSE
UIO - User Interface Organizer
(Note: for UIO to work properly you have to install Visual C++ 2019 using protontricks. Instructions: )

Worked for me as well! Thank you very much, I owe you one!

In order to install Visual C++ 2019 (the OP says 2015-2019 but I just installed the last one at it works) I used prototricks.


    Install protontricks

    Launch it from Steam App Launcher and select Fallout New Vegas and click OK

    "Select the default wineprefix" and click OK

    "Install a Windows DLL or component" and click OK

    Scroll all the way down to find VC++ 2019
                   Done. Just wait some seconds, and if you want to check if VC is installed, just repeat those last steps and you will find it checked


It works like a charm with proton 8.0-5 as compatibility mode and last version of UIO.
Now I can zoom with scopes like a boss.

(Thanks to Elelm92)

kNVSE Animation Plugin
ShowOff xNVSE Plugin
KEYWORDS
MCM
NV Compatibility Skeleton
Improved Console (NVSE)
lStewieAl's Tweaks and Engine Fixes + ini (or use mine)
JIP Companions Command and Control
Vanilla Animations Weapon Scale Fix
ISControl Enabler and Ironsights adjuster (now ESPless)
Fallout 3 Weapons Iron Sight -Modders Resource- V1dot3

Install all the files manually, then sort.

Section 4: Gameplay/Overhaul
Manually download the following mods:
Titans of The New West 2.0
Sweet 6 Shooter Perks - NV
JAM - Just Assorted Mods
Enhanced Movement
FPGE - Functional Post Game Ending
The Living Desert
YUP
JIP Fast-Travel Anywhere with Random Encounters
Claim the Mojave (and the Capital) (Make sure you grab the living desert patch from the optional files and DO NOT install the patch from the FOMOD)
Mojave Squads
Just Independent Crashed Vertibird Power Armor Training
Auto-Save Manager
FPGE - Rebuild Vegas
FPGE - Lonesome Road

Optional but HIGHLY recommended:
Cyberware 2281
Fallout NV Cheat Terminal Redux
OG Item Browser Use ESP-ESM Explorer ESPless instead.

CyberJAM
Leveled DLC Delay
http://
Section 5: Animation
B42 Interact - Animated Items and Interactions Framework - ESPless
Iron Sights Aligned
Viewmodel Shake Fix - NVSE
Smooth True Iron Sights Camera
B42 Weapon Inertia
New Vegas Animation Overhaul - Guns
Hit - B42 Inject Animation Pack - Season 1
Hit - B42 Inject - Water Animations
Hit - B42 Interact Animation Pack
Hit - B42 Inject - Meat Animations

Section 6: Weapon/Armour Mods
Tammer's NIF-Bashed Weapons Mega-Pack (non nexus)
Tammer's NIF-Bashed Armor Mega-Pack (non nexus)
Vlad (Tammer Vendor)
Dr. Quarton (Tammer Vendor)
Roxxi (Tammer Vendor)
Honest Herb (Tammer Vendor)
T-60 Power Armour (don't use the esp)
T-60 Power Armor as Normal Power Armor
Fallout 3 Weapons Restoration
Tribal T-51B Helmet at Wrecked Highwayman

Section 7: Patches
Tammer Armors TOTNW Patch
T-60 Power Armor as Normal Power Armor - Titans of The New West Patch
Havasu Blues Bugfixes

Section 8: Companions
Most of these are joke mods or are lore unfriendly.
JIP CCC Avatars for Riddick - Boba Fett - Nick Valentine - Duke Nukem - and Jack from Mass Effect
Requires you to have a gunetwork account, and the individual mods are linked in the requirements.
The Postal Dude - A Cynical Companion (download Postal Dude Face and Outfit)
Dagoth Ur Companion
Caesar - A Functional Post Game Ending Companion

Section 9: Quests
My selection of (relatively) space conscious quest mods. Pick and choose which ones you like.
Dry Wells - Legion Expansion
Havasu Blues
Casino Heists - New Vegas
Into The Deep

Section 10: Joke mods
Justice Matters Magnum - A Better Call Saul Revolver
Nerf Doublestrike
Wendy's
Lore Friendly Immersive Legate Lanius Helmet Monster of the East Redux
Normal Pills - New Chem
Abraham Lincoln Action Figure Weaponized
WordleHack - Wordle as an Alternative Terminal Hacking Minigame
BIonicle Masks (WIP)
Osama Bin Laden as Mr. House
Skibidi Toilet Armor thing - god help us

Section 11: Visuals
All Optional and Minor Stuff
Global Imposter Region - GECK Imposter region addons
Freeside (rotating sign)
Nipton Black Smoke
Volare - Animated B-29 Superfortress ( b29- boomers- flying airplane)
Hoover Dam Jets Restored and Distant(GIR)
Light Pollution Manager - Consistent Light Pollution (GIR)
Vanilla UI Plus

Section 12: Configs
I have my stewie tweaks config, or you could configure it yourself.
ABSOLUTELY NECESSARY: Turn of JVS in the JAM MCM.
I recommend binding one of the back buttons to F5 and another to ~ for quick saving and the console.
I also recommend using a keyboard and mouse controller config.

With that, you should be ready to play.