First, we need to damage his capability to jump or at least weaken the ability.
We made some close encounters with Mezzomorto, CIC may analyze the data we have collected so far and figure out a way to weaken her ability to jump.
According to those analyzes we may spam her with EMP attacks maybe hoping it would damage its jump engine.
In every situation we need a bait (planet, ship etc…) to lure him out of his comfort zone. We might give Mezzomorto an easy target to get his attention.
Another point that is open for exploits is his ego. It seems that Mezzomorto feels untouchable with his ship and fleet. We can exploit that as well, because while we are taunting and lurng him into trap he wont be looking around to see whats going on behind the curtain.
We need to keep Captain Jinx on sight as well. She is a total wild card. Her ship may not be as strong as Crooked Star yet she has proven herself to be dangerous in the last mission.