Overview
FNP-9 is a hit rate focused support HG. Her tilebuff has good coverage from position 4 and provides a decent enough rate of fire and a large amount of accuracy. That combined with her skill that debuffs enemy evasion allows for the DPS to land more shots on more evasive targets.
However, RFs and ARs have inherently high accuracy, and MGs don’t really benefit from rate of fire nor should they be fighting evasive enemies in the first place. Stacking more accuracy really only becomes a concern late-game when facing against nighttime armored evasive units. In that situation ARs can just equip a PEQ instead. If one finds themselves facing nighttime evasive targets with RFs, FNP-9 can be an option, but better options such as SPP-1 and Type 59 would likely be available to them by then.
So while she does not perform it badly, the niche FNP-9 falls in only really applies in more late-game fights, when better options are readily available. FNP-9 is usually just not worth the investment.
Pros
Good Tileshape
Her tile layout allows FNP-9 to hit the entire formation at position 4.
Cons
Low HP
For an already squishy doll class, 300 HP is low for a HG.
Niche Hitrate Focus
Outside of specific late-game encounters, FNP-9’s accuracy niche would see very little use.