This mod is titled ‘The Little Engine that Shouldn’t -- Steam Deck config (OLED)‘ and it’s clear that you shouldn’t expect any miracles. As the title suggests, all testing has been done on the OLED model, but you should have similar results if you own one of the original LCD devices.

How to install and use this mod:

1. Log in to Nexus Mods (make an account if you don’t already have one)
2. Download the config file
3. Place the config file in your steamapps/common/MonsterHunterWilds folder and set the file permissions to ‘Only View’
4. Before launching the game, ensure you are using Proton Experimental or GE Proton 9-25
5. Edit the MH Wilds launch options to include the following command: __GL_SHADER_DISK_CACHE_CLEANUP=1gamemoderun %command%
6. It is recommended to lock the framerate to 30 FPS and set the GPU clock to 1,600MHz.

When you go to the mod on Nexus they will have further instructions to help out the game. It's not the best but runs better between 30 to 40 fps.