Can you explain why editing an ini or using the console command is not acceptable?
A big chunk of games I play also enter fullscreen mode when run, but only because the game’s config ini files have that config set. Don’t you just update the games ini files and ship it with that config? Just as many games also actually launch in a windowed mode, but then switch to fullscreen.
If you cannot use those 2 methods for whatever reason, can you explain your situation and offer an example of what you do need.
Unfortunately, while it may be added in the future, at present the only options you have available to you are to edit the .ini file or run a console command. Even if/when these settings are added to the project settings menu, they will still fundamentally be editing the .ini settings to accomplish this task. Is there a particular reason that .ini editing is not optional?