Fantastic question- I assume you mean the kid reacting to their respective flower-
Sally's probably pretty scared of Aqua- Though considering most of Aqua's uh- stuff is directed at Seth, She'd be okay.
Palmer would probably really respect Orange's desire to get stronger and be brave- They'd probably spar.
Lucky and Seth I think would either completely understand each other or outdo each other depending on the first impression.
Sunny and Green would get along. Green's awesome dude.
Luna would probably hate Blue at first. Him being GNC would be awesome but the fact it's ballet would just sort of turn Luna off the idea as a whole- finding him pretentious as hell.
Clover and Yellow would naturally get along- They're very similar characters generally.
As a bonus Flowey would ofc detest flowery.