Fire Emblem sacred stones cheat codes

I have spend the entire day searching for cheat codes for this game because of a hack that has characters that are way too weak so I want to use cheats for Stat boosters but no cheat seems to work.
I’m using Pizza Boy GBA. Cheats worked fine in hacks with FE7 but FE8 cheats don’t seem to work at all.
Can anyone help with codes for Stat boosters for FE8 and a mini guide on how to activate them?
Thanks.