Hi, I'm designing a homebrew race for a campaign, and I've run into a bit of difficulty. I'm trying to have it so that a character of this race is able to use certain spells at certain levels (e.g. knowing how to cast Faerie Fire at third level), but I'd like it so that the character can use the spellcasting ability of their class to cast the spell. For example, if a character chose this race and was a ranger, they would use Wisdom as their spellcasting ability for the innate racial spells, but a bard of the same race would use Charisma. Is there a way to implement this? All I can seem to do is set the spellcasting ability modifier within the homebrew race, not have it be contingent on the character's chosen class. I can think of some convoluted and imperfect workarounds, but I'm hoping there's an easier way. Thank you!

There is no way to have it automatically tied to class. You would have to do it the same way as the newer races do with a choice of Int, Wis, or Cha. I gave instructions for how to do that in the Subclasses & Races FAQ #17: (https://www.dndbeyond.com/forums/dungeons-dragons-discussion/homebrew-house-rules/131411-a-homebrewers-how-to-faq).

You will have to use 3 different options, one for each stat.