I have seen some running around with this... How do I get? Is it like the other boss costume weapons and can only be made at the UNION division hq?
I think it's like other boss costume weapons. you need to get the materials in the last dungeon, I think, and craft it.
Edit: It is craftable, but idk where you find those "Irina's Punisher Bow Fragment"
Subjugation Irina can drop the fragments and also the punisher weapon skins. Even the fragments are kinda rare, so you'll have to do a lot of runs for it.