I'm planning to also add:
agender, genderfluid, genderqueer, aromantic, polyamorous, polysexual, demigirl/boy, and leather designs!

If anyone would be interested in a flag i haven't mentioned, let me know!

I'm looking into getting stickers made locally so i could ship them myself (probably via my Ko-fi shop).

For now though, RedBubble is the easiest option for me. The artist's margin may be very small, but if anything, it does help boost my confidence. ^^