So I have Earth Bound and I need help with his TC and species. I was thinking for species a Scribble Experiment 886 who looks like Giygas or a chibi 585 for BuzzBuzz?

As for his TC I kind of only got as far as the journey to Scaraba, but if you can think of something please let me know!

I think a Scribble 886 is a very fitting pet for EarthBound. :) As for pet treasure, maybe some more equipment to represent Poo?
Sword of Kings:

Cloak of Kings:


Diadem of Kings:


Bracer of Kings:


I hope this helps!

It helps a lot, I had forgotten about Poo's equipment! Thank you!

Glad to help! :D I think I might have found something else that can help. Remember the Territorial Oaks in Peaceful Rest Valley? This might be a good representation of them: