i’m legit confused, if you don’t want to actually play the game, why don’t you just use the save editor, or GDstash, or the premade template char Medea linked?
the way i’m reading OP and your subsequent reply to skips already existing is “i don’t want to do even that”, which makes it sound like what you want isn’t really playing the game (since it comes of sounding as this unbearable chore) but “test” builds?
and for testing builds we have all sorts of modding options available - heck you don’t even need to download tools or premade saves, you can just go in custom mode and use console commands Console Commands Reference