

This game should run fine also on a potato pc however I encountered slowdowns and performance issues even on a decent spec laptop. But don't get me wrong, performance issues doesn't affect the gameplay, at least on my configuration, and the game is still playable from start to to finish.
At the time of writing this, newer versions of Proton have been released but when I played the game the latest version was Proton 9.0-3.

Fps issues at certain points in the game but still playable.
It's fun.

Game seems to work perfectly for about 5 minutes, and then the screen freezes, goes black, or the game crashes. Other versions of proton didn't seem to fix this.
Short and simple game with small puzzles.
Once, the game started stuttering. I restarted the game and it became OK.

6.21-GE-2 GloriousEggroll
protontricks is used to solve flickering with KDE taskbar
- Run
protontricks 885810 winecfg
- Select tab "Graphics" and uncheck "Allow the window manager to decorate the windows" and "Allow the window manager to control the windows"
protontricks
fix flickering with KDE Taskbar. But it makes games always on top of screen, so you can't escape fullscreen conventionally by Alt-Tab or switching to different KDE Virtual Desktop.
FPS fluctuation between 50-75 FPS, barely noticeable though
Works perfectly with Proton Experimental

By using PROTON_USE_WINED3D=1 %command%
with Proton 6.3-8 I was able to get a decent framerate. The game is completely playable like this.
The game performs really bad compared to windows.
I could not play this game comfortably on an old laptop, and the solution provided by 晴れ | sunny doesn't seem to work after the last update (might still be worth a try for you). However, I had a good experience on my current machine, with some screen tearing issues that I resolved by keeping my compositor (picom) on during gameplay.

Input lag and frame drops
This post in the discussions forum for The Witch's House MV provides a link to a custom RPGMV port of this game for Linux. The attached Google Drive folder in the post is NOT translated to English.
I downloaded the .7z file and extracted it to my games directory for Lutris. Then, I copied over the following files and subfolders from my Steam installation of the game into the new Witch's House MV directory:
locales, www, nw_100_percent.pak, nw_200_percent.pak, resources.pak, and package.json
All to ensure that the resources needed for a full English translation were available.
Then, I launched the game through Lutris with the Linux Native header, and the game runs silky smooth. This is only intended for those curious enough to get this game working perfectly on Linux. This is NOT intended as a primary fix.

It's too laggy, audio clips too much. And input has a noticeable delay.
It clips often
Extreme stuttering