(Tl:dr: I've got a team I'm happy with, struggling to decide last slot. Current options are on the 2nd image with some pros/cons. I'm also open for general teambuilding tips but im mainly looking for this specific 6th mon. Also now considering having a dual mega setup but unsure with who)
During the time Champions has been out I've been purely running M-Froslass teams since I've always enjoyed snow teams and I'm happy that it feels so good in this format. I've tried different teams and spreads and ended up with this setup (mostly taken from teams I've found online with some tweaks). I've managed my way up to MB rank 3, which is better than I expected after not playing VGC for like 3 years.
The overall idea is that it has some mons with bulkier spreads that can already deal enough damage that damage investment isn't required, and if Aurora Veil comes up, the team becomes surprisingly tanky while still being able to dish out good damage.
The main issue I've had is the last mon, I know I need a support mon since my team is very damage-heavy. My main matchup issues have been M-Gengar/Sableye teams as well as trick room teams, so I've wanted to get something that can help me against those while also having general utility. I've tried 3 mons which I have liked, but all of them have some flaw and just don't feel exactly right.
I've put these mons on the 2nd image with my thoughts on them, and I would like some help in deciding which one to put, or if it would be best to put something different entirely. I am also of course open to suggestions about changing other mons, but at the moment, I feel like all the ones I have cover a weakness that I really want covered.
Thanks!