I don’t see why you need this setting for your account? If you’re afraid of accidentally purchasing something in-game, Roblox already implements a delay to when you can click the “Buy” button of a product in-game.
I have never seen this specific setting before for in-game purchases. Only saw one for purchasing Robux with real money.
I just enjoy this blocking pop up in game, some game spam you with purchase gui each time you respawn. And just in general i like having it disable as i don’t want purchase prompt
This is more of a game specific issue here. Most games (aside from cashgrabs or scam games) don’t practice this, so it shouldn’t be that big of an issue.
I don’t really have any other solutions for you. I don’t recommend you to use 3rd-party apps to disable purchase prompts for you. You’ll just have to live with them, honestly speaking
Honestly i would probably just not play these games. I mean it would be a good option to “not show ingame purchases” as a setting but for now that’s not a thing