SFSE works fine for me, no issues at all. Make sure you download the latest version, to be compatible with the latest Starfield update.

I’ve placed the dll and the exe next to the Starfield.exe in the game folder. And changed the Steam launch parameter to

bash -c 'exec "${@/Starfield.exe/sfse_loader.exe}"' -- %command%

GTAV works better with AMDVLK, as one of the very few games out there. You could give that a shot, but be aware that AMDVLK often gets selected as default, so having AMD_VULKAN_ICD=RADV in your global Env. Variables are a good idea.

And then launching GTAV with AMD_VULKAN_ICD=AMDVLK %command%.

That was not Linux Mint but Pop! OS.