Looking to make a custom magic item that increases the amount spells you can have prepared by 1 when the item is attuned + equipped.

Would this be possible? If possible I would like to limit it to a specific class's spells too.

I’m afraid that is not currently possible, no.

Ah I see, thanks for letting me know tho

You can fake it as part of a Race or Subclass if that helps:

https://www.dndbeyond.com/forums/dungeons-dragons-discussion/homebrew-house-rules/138855-could-use-some-experienced-advice-on-how-to-setup#c2

Ooo nice workaround!

Thank you very much!

If I was to do this via a SubClass, how would I add the extra prepared spell?

Would it be a class feature? If so would it be a Class Feature Option?

Just add a subclass feature, no option necessary. That Spells subform is available under class features.

Without any home brewing, a magic item that effectively increases your spells prepared is called a "Wand".