If anything, dirty bomb has a lot of variety. You have medics, you have snipers, you have mercs tham make things go boom, a black man killing people by throwing his balls at them ( ͡° ͜ʖ ͡°), mercs who can lead a push, mercs who can stop a push and phantom. But what about an electronic warfare specialist?
My suggestion is:
Name: Erica (debatable)
Gender: Female
Nationality: German
Role: Electronic warfare/Assault
Health: 80
Sprint: 450
Weapons:
Primaries: Empire-9 (stock), Tølen MP, MP400
Secondaries: M9 (stock), Selbstadt .40, Caulden
Melee: Beckhill Combat Knife (stock), Cricket Bat, Stilnotto Stiletto
Abilities:
Primary: A pulse that disables healing/ammo stations, mines, turrets, kira’s and arty’s designators and phantom’s cloak for 5 seconds within a certain radious, even through walls. It will have a 2-3 seconds activation time and any damage taken during that time will disrupt it.
Secondary: A riot shield, with 250-350 hp worth of damage absorbing (but if something that does more damage like a grenade hits it the merc won’t take damage from it even though it exceeds the shield’s hp, you will just lose the shield). While you have it equiped you can only hip-fire and possibly have some accuracy penalty. She also moves at the same speed as a Rhino firing his minigun.
Tertiary (Optional): Being an objective specialist (to go along with her being an electronic warfare specialist).
From her abilities her role is pretty clear, being a tank. You deactivate your enemies’ deployables on the other side of the chockepoint and lead the push with your shield to take the hits for you teammates. While a very useful merc if supported by her team, on her own she lacks the ability to “bite”, since she might as well have a nerf gun as a means to deal damage with her selection of primaries.
PS: Sorry if my english is bad.

. But here is the thing: