It's basically like maledicting a warrior: it does impact their ability to dodge and deal damage.

The flipside of that being, just like a warrior you can gear to counter that strategy if you're of a mind to as a shifter. Just as boneshatter can be pretty good against a warrior, but then you run into someone geared like Eleagra and not only do they not lose a weapon from boneshatter, you need another -15 STR to even get them off max.

Regardless of those considerations, some maledictions cause major or minor shifting trauma, which is a very useful tactical consideration, assuming the shifter can't just beat you straight up with the form they first attack you in.