To be hones I always tough that ninja is already "too prepared" for pvp, they have a lot of useful skills for this kind of contet and when I saw that they have Overwhelm too I was a little frustrated, Monk could have really a big difficult in pvp but atlest with personal LB and shoulder tackle they can become an instant caster killer.

Ninja can already dind with Hyoton and run away or run in with Shukuchi.
Also they have even Weapon Throw that up to me is a skill very important for Monk and maybe dragoons but ninja that has a normal higher speed, up to me get a little too advantaged.

If I was the dev I woulded leave to ninja only one among this 2 skills, or atleast remove/change the Stun effect from Overwhelm.
But, just my opinion