I originally built a decently successful team with jirachi+Diancie, but I wanted to try out a variant with kang and see if it could be more successful.
First, let me explain the team. It's focused on setting up a 2-mon sweep late game, with something like serperior+blaziken or Kang+Greninja, etc. Thus, the entire team is focused on preserving momentum, with picks such as 4-attacks life orb deoa, Fire Blast with only 241 speed blaziken, and maxspeed togekiss. Generally, the team has issues with talonflame, but you do have deo-a espeed to nuke it after it takes some recoil, and togekiss, imo, counts as a tflame counter.
In my experience playing this team I've played something like 10+ games (sorry can't post replays) with other players in tours/challenges, and only lost to hax (stuff like serperior missing a leaf storm, getting frozen) or fullroom, which seems to give this team a lot of trouble, but I've only played one game of that so I couldn't get to test it extensively. Sun-boosted venu is also a big issue, but it's difficult for sun to lead correctly and properly stop your momentum when they have to wait a turn to get the sun. Once Blaziken gets started or Togekiss sets tailwind, it's generally very difficult for sun to recover. A wellplayed bulky thundurus can also give this team trouble, but unless it gets a lot of full paras you'll be able to nuke it the first turn it's out, then keep your paralyzed mon as a really slow attacker that your opponent still has to respect. And since people are bad and not using protect on thundurus, Kang is a good answer to it as well.
Kang:Standard Boring
Togekiss: ok I run lots of speed because I forsaw having lots of issues with sun, breloom, and diancie. Thus, HP Steel (which is a great pick because no diancie is going to expect it and no diancie is going to just protect in front of you while you potentially set tailwind) is a neat option to snipe diancie-mega. I didn't want to have to run goggles to get 2 spore immunities, so instead I opted for a higher speed togekiss. Initially, I only crept to around 270, but then I realized there were important speed tiers at 280 such as hoopa speed tie and other setup-mons (blaziken, volc) that are in that range. Outspeeding those bulkier char y / kang sets is hilarious as fuck too.
Serp: Standard. This mon is kinda of weak but is excellent at destroying waters. What typically happens is I have to play around their team and somehow give serp room to pull off a leaf storm (ie a sac or a good switch or togekiss) and then it can start nuking everying
Greninja: Also Standard. I considered running taunt here but felt it wouldn't be useful against good tr players, so I decided against it. Ice coverage is very nice for nabbing amoonguss. Anyways, greninja is a great option now with talonflame gone and always pulls its weight, while having several matchups that it perform better in than keld, notably diancie
Blaziken: The team really started when I thought of blaziken sets that would have staying power, that is being able to remain on the field rather than switching after someone switches in their washtom on your overheat. HJK and Fire Blast thus are the options I opted for, while borrowing lots of speed evs to put into spA so that Fire Blast can still ohko Aegis. I really like this set, as once it gets going it really supports that team idea of momentum gains.
Deo-A: life orb deo-a is a set others and I have been thinking of trying, so I tried to make it work here. I use life orb because 1) you get massive nukes, being able to ohko washtom with psycho boost among other things and 2) because I want clean switches. In addition, I went with 4 attacks rather than protect because protect does no damage Deoxys suffers from 4mss in its coverage moves. I didn't want to be unable to hit the switchins 50% of the time, so I went with 4 attacks. Also, in situations where I want to protect (seeing fake out, being outsped) I should really just be switching anyways. I know it's natural instinct of all players to use protect on everything we can, especially deo-a, but a non-sash variant really shouldn't in my opinion, and this set has definitely carried its weight.