I'm trying to do the nidoran manip and I've heard you have to hard reset instead of soft (A+B+Start+Select)? The guide says you have to use a hotkey to hard reset but I can't figure out how to do it. Can anyone help me please?

You do have to hard reset. If you're using Gambatte you should be able to bind a key to hard reset.

Thanks I’m just blind and dumb lol. I took a close look and finally found it

By the way, don't forget to use a GBC bios with Gambatte to properly emulate RNG.