after i looked at the OU 1760 statslucario had 1.5% usage, volcarona had 2.6%, i can see they dropping. manectric and gardevoir, however, had both 3.5% usage this month, threatening to move up.
just theorymoning, i can already see volcarona being banned. it is actually a great sweeper even in OU, the problem is that it has A LOT of counters there. in UU i can only imagine, from the top of my head, sp.def arcanine. there's probably more, but even then i doubt it'll save volca from the axe.
lucario seems kinda controversial though. SD is extremely powerful, OHKOing pratically anything with close combat and being hard to revenge because of extremespeed, while NP is a special sweeper that beats pretty much all of the special walls (florges, umbreon, aggron, snorlax, etc); and with both sets being really dangerous, it'd be almost like a coinflip and he might emulate mega lucario in OU. however, with those defenses it really isn't that easy for he setup, and it might (i said might) be possible to beat it with prankster WoW from sableye/mega banette, scarf users that can take extremespeed or vaccuum wave like chandelure.