Title, basically. You have balanced tanks to be absolute gigabosses in 5v5 and the 150 hp nerf in non-role queue modes isn’t nearly enough to make these heroes unproblematic in FFA. Just disable the role, because you’re not going to put in the 35 seconds to nerf them more.
They used to be okay in arcade modes. I actually felt pretty confident going up against a Junker, Orisa, etc, as Kiriko in a duel. It’s the headshot passive that caused everything to fall apart more than anything else, I think.
Simple idea;
Play the tanks