protontricks-launch -h neither offers an option to set the working directory nor has any hints or clues which one it is about protontricks HOT 4 OPEN

The working directory is set to the selected app's installation directory, but only for custom commands and protontricks-launch. Winetricks commands instead use the current working directory.

protontricks-launch --appid <APPID> <EXE> is more or less a shorthand for protontricks -c "wine <EXE>" <APPID>, so depending on your use case you could use protontricks -c "cd <PATH>; wine <EXE>" <APPID> instead.

The current situation is admittedly confusing. It might be better to remove this functionality and let the shell/desktop environment take care of the working directory in all cases instead. I don't recall there being any specific reason for this besides it being a tad more convenient when running protontricks -c bash <APPID>. Some 3rd party scripts might rely on this behavior, but hopefully not.

from protontricks.

An option to control this behavior might be enough if you don't want to change the default. Maybe I'm wrong about this, but wrong working directory errors tend to be fairly obvious to any user who has used the terminal before, which seems to be the crowd that would use protontricks-launch(??). So I think most people would look in --help at that point to figure out how to set it. But maybe I'm underestimating the potential confusion for others, I'm not sure.

from protontricks.