When someone leaves a competitive match there should be an option at spawn (after death) to have one team member have almost Ana-like buffs. A supersoldier with higher health (through damage reduction, stronger attack and maybe faster speed). I don't think they should be as strong as an Ana ult, but 75% would be a good starting point.

After someone leaves and a member of the team dies, they can choose to apply the buffs to themselves.

Pros: Counters people leaving by buffing existing members. No need for 6th member. Buff can be balanced so that it doesn't give advantage to leavers team. Could be applied multiple time (3 leavers = 3 remaining supersoldiers) Can be removed if player returns. Can choose team member to take buff e.g. Tank to hold point or flanker to break enemy. Or just the person with gold elims.

Cons: People might find a way to abuse, especially Smurfs, so that a higher level character gets the buff. Season 2 might prove me wrong. Still 5vs.6 so tactics and flanking would be difficult. Focus on remaining players decision as to who uses it - might be first death gets it and this might lead to snowballing, but if limited to comp only some resemblance if team work should exist. Person would get focussed more (faint Ana glow)

I haven't seen this before so apologies if you have.

Let me know what you think.