I hope to change my pet Archaeology from Graveyard Sheeta to Graveyard Ruffie. May I know is there any potion or anything that can change it? Thanks in advance.

You could get a Miracle potion II for CSC. Or if you don't want to spend CSC you have to get a Ruffie potion and a Graveyard potion.

Thanks for letting me know, I will prefer the second choice^^"

Good luck! :)