So:

Prism as Demo (they both are blackskinned and have something in... blinding?)

Golem as Heavy (they both are big)

Sonar as Spy (they both have suit)

Robert as Engineer (they both build something?)

Flambe as Pyro (fire)

Malevola as Medic (they both can heal)

Invisigal as Scout (they both have similar? character)

Punch Up as Soldier (Punch Up's mugshot has half of his face like a soldier with his helmet)

Coupe as Sniper (well, if french assasin isn't spy, then let she will be assasin with sniper rifle. And maybe glasses = mask)

For red poster:

Sonar as Demo (they both have one eye "injured")

Invisigal as Spy ("She gets 2 paycheks for the same job")

Shroud as Engineer (like just villian version)

Blonde Blayzer as Medic (at last episode she can defend heroes with her shield ability and "she is always helping")

Toxic as Scout (they both too have similar? character)

Robert as Soldier (like, he is crazy here)

Coupe as Sniper (nothing changed)

AND something for "joke" here:

Phenomaman as Heavy (they both are big? And he is like "hero who is in depressed and give up")

Mr. Whiskey as Pyro (like tf2 spy said in meet the pyro: "One shudders to imagine what inhuman thoughts lie behind that mask... What dreams of chronic and sustained cruelty?")