u/how-about-know

I am fairly new to VGC (Played ladder on Sw/Sh but didn't play S/V much) and have never played in a format with megas. I have been wanting to experiment with some of the more obscure megas. Do either of these guys have a potential niche? At base 100 and 75 speed, respectively l, they would definitely need to be on a tailwind team, or maybe tail/room for heracross. Any recommendations for team builds, archetypes, or partner/support mons?