I'm having thoughts of replacing my Roselia for another grass type pokemon (temporarily), since I still haven't got the shiny stone. I just beat Shade if that helps to determine which pokemon I should use later on. Some grass type pokemon I have in my PC are....
Petilil
Hopip
Pumpkaboo
Bounsweet
Carnivine
Fomantis
Personally I'm leaning towards Petlil to spam Petal dance + Own tempo, Pumpkaboo just because it seems bulky, and Bounsweet since its a physical attacker which I need a bit more on my personal team.