Good end game teams and movesets?

[Aseris2003]

Ive gotten to victory road and i wanna know a good team for endgame fights.

[Jason86JR]

Imo, any team is good, but make sure to have broad element coverage and make them at least lvl 65, EV trained since

Spoiler

 iirc, the normal lvl is 70 and the highest is about 80

Having one or two tank pokemons is also a good idea.

[HuckebeinTheRaven]

My recommendations:
Metalynx, mega or not (can tank just about anything but fire attacks, plus it is a good extra counter to Rosalind, as it can learn Night Slash)

Yatagaryu, since with Outrage/Dragon Pulse/Draco Meteor plus Thunder there are close to no pokemon that can resist a hit from it.

Nucleon, with Hyper Voice at the very least, since against everything except Steel and Nuclear types it counts as a 180 - 360 base power attack (depending if single or dual type)

Baariette, with at least Foul Play and Drain Punch. I'd also recommend making this your mega, as Blood Lust + Drain Punch + the incredible defenses this 'mon has makes it nigh on unkillable, and it's Attack stat means it hits like a semi-truck.

The rest can be more along personal preference, although Luxelong would be another recommendation, since it's dual dragon-fairy type has a lot of possibilities, especially against Vaeryn.

(Note, I mention these gym leaders because you face them in the Championship as well)

However, that being said, all you really need to do is create a team with the best offence/defense coverage possible that fits your preferred playstyle.

I just got to the championship myself, and as it stands my own team is:

Metalynx (Mega)
Yatagaryu
Baariette (Mega)
Nucleon
Pajay
Glavinug

With
Drilgann (Mega)
Luxelong
Coatlith
Brainoar
Garlikid and
Kiricorn (Mega)

being held as reserve options

[Blue]

My first playthrough I used a Nucleon (before I knew just how OP it was), it sliced through the Championship like butter, none of my other pokemon even got a move inbetween the OHKO's. I consequently don't really use one since then but if you're stuck or not confident in your team then Nucleon can be a good Hail Mary.

[Lord Windos]

A good Dragon will save you team, no matter the Problem! Traction is great for its resistences and ability, while Fafniter's bulk and balanced Attack stats and good offensive typing make it a true Juggernaut. Or if you want to get cheeky with status, Dunseraph is the 'mon for you~ Luxelong is great for a number of reason, the main one being that its super easy to turn it into a super cleric, the likes of which that would make Slyveon green with envy.

Those are my suggestion, so take them however you may~.