|Good to have
Supernova is a shotgun pretending to be a handgun to go along with her shipmate GSh-18. She’s one of the most supportive shotguns available and she enables some real dumb stuff. You want to use MGs at night? Well, her skill allows for that. Do you need a little more defensive capability for your shotguns? She brings that too, all in a kancolle-flavoured package. Honestly, she’s not an automatic pick on every team. You’re likely going to have to drop a MG in your formation to make use of her fully, which can be an issue.
Her two main draws are her movement speed and her MG buffs. Her roller skates allow her to go almost as fast as a handgun, but not quite. Not much else to say about that, but main reason to take her is the MG buffs she provides.
While crit rate is nice, the accuracy buff she provides to MGs is fixed. This means that MGs are entirely usable at night. It bypasses the accuracy penalty that you would normally have with no PEQ. While not the most relevant thing currently, you definitely want to have Supernova in your back pocket for the future.
|Can buff other shotguns, but isn't great herself
OK, your mileage may vary a lot for this one. Her Armor isn't great and she herself isn't exactly super tanky without her skill up. On the other hand, her skill might buff your other shotgun(s), so it may be useful for that.