What sized tanks? What triggers do you want?
For example - Blueline and Undulated triggers probably shouldn't be kept with any fish, let alone other triggers. I tried a blueline that murdered everything in it's sight and it was only 4 inches. Undulated are similar in temperament. Clown triggers are nasty but do very well for some time before "snapping". This can occasionally be "mitigated" in a very large tank. My clown trigger is about 4.5 inches long and a great community fish in my 500 gallon ten foot tank but they're known for deciding randomly that they don't want any tankmates and killing them. Others swear they're great community fish forever. I am guessing at larger size this is a bigger risk, particularly in a "smaller" tank.
Humu and Rectangulus triggers (close cousins), Niger, Pink Tail, Blue Throat, etc. can often be kept together. Adding at the same time increases your odds. Adding triggers or mixing them in general is a big risk because they can do a lot of damage quickly but I've mixed the triggers aforementioned together before in 180 gallon tanks.
Tankmates: Large angels, squirrelfish, puffers (if large), large tangs, large wrasse (such as thalassoma genus), larger butterflies on occasion (many are peaceful try to find "semi aggressive" butterflies), sometimes large dwarf angels, larger more aggressive halichoeres wrasse may work (such as a large melanarus wrasse), etc.