No. Don’t trust the OGL. WOTC tried to “revoke” the OGL last year in a way that would fuck over all 3rd party publishers. People raised absolute Cain and WOTC kinda sorta backed down (kinda sorta) but there’s no guarantee the OGL is safe moving forward. To the point that Paizo (makers of Pathfinder 2e) are reprinting all of their Pathfinder 2e materials to remove anything that could remotely depend on the OGL.
If you want something more trustworthy than OGL, look into ORC.
Here might be a good start for you: https://wiki.rpg.net/index.php/Open_Game_Systems#Open_Game_License
Just because of the nature of those games, I would speculate that the page above is just a fraction of what is available.
No. Don’t trust the OGL. WOTC tried to “revoke” the OGL last year in a way that would fuck over all 3rd party publishers. People raised absolute Cain and WOTC kinda sorta backed down (kinda sorta) but there’s no guarantee the OGL is safe moving forward. To the point that Paizo (makers of Pathfinder 2e) are reprinting all of their Pathfinder 2e materials to remove anything that could remotely depend on the OGL.
If you want something more trustworthy than OGL, look into ORC.