Ganon is a killer, Find a teammate that racks up damage and survives (I.E. doesn't get juggled easily and is quick ). Lucario, Falco, MK, G&W, Toon Link, Diddy Kong, Sonic, Wario.
Ganon gets the kills and just hits off other peoples Combo's. You are less likely gimped in a Team game, but you still want a teammate that can chase people off map in case you are put in a gimpable situation, not all of the above are good options for this, but they can. Your teammate needs to be the one on offense while you wait for the opponents to be distracted or bait spot dodges, air dodges or rolls.
Combo'ing with teammates, Falco is the best. Gerudo Laser lock is awesome you can do it when you knock one opponent off the map, 2v1's or when you just killed the other opponent, get the free F-smash or Warlock punch, easy kills. also his Chain grab is awesome for damage, Combo off it with Dair's also instead of Falco spiking him off the map you spike him, either jump over falco to spike or hang on the ledge and short hop the spike.
MK is good hit aerials when people pop up out of the tornado Fair and Bair work well. When MK gets someone off the map set up a defense wall to protect that side while MK does his gimping. People get careless when trying to help teammates so wait and punish. MK can also save you from getting gimped.
Diddy is awesome cause you can use Banana's he wracks damage amazingly and you get easy kills when they trip, he can keep opponents off you with banana's and he is quick and elusive.
Lucario just doesn't die lol his Fair can save you from gimps and he powers up if u start losing.
Toon link survives and wracks mad damage, people will get shield pressured big time from projectiles so you can get hits in easier.
Sonic, doesn't die faster then hell wracks serious damage.
Wario and G&W both can kill and wrack damage as well as survive they are great teammates.
These are just some Idea's. I have used Ganon in teams at tournaments before and done quite well. Avoid heavier teammates like Snake and D3 they get combo'ed easily and u can't chase to help them.
Control the center of the map with Ganon, let your teammate be offensive and chase opponents, learn to pin them onto sides of the map so you can predict rolls into Dair's. Gerudo's work well in team's you can chain choke and even bait teammates into your attacks because they will run to help their teammate. plus you get super armor on the grab lol. Stick to quick moves I.E. jabs and tilt's and your faster aerial's. no need to charge smashes or anything cause you can kill teammates.