I want to say u can, because as an example Infernape Lv X says you put this on your "Active Infernape" so Weather Infernape is a Gym leader, or special team's (Elite 4 for example) it is still an active Infernape.
Elite 4
in elite 4.
elite 4
Repeatedly battle the Elite 4 with high level Pokemon with the Pokemon you want to level up holding an exp. share.
the elite 4
The elite 4's Pokemon the first time you beat it the level range is 40-55. After you beat all the gyms the level range is 50-75.
Well,Level 70-100 Is A Good Level To Beat The Elite 4.
the elite 4
get all your Pokemon at least to level 65
elite 4
get a bunch of Pokemon lv 50 and above
I would say geting your pokemon to a level 80 or higher.