>>16782415sturdy only kicks in once though. it's a one-and-done like the focus sash.
So.. arguably Sturdy Shedinja is an interesting and certainly not broken build. He's got 1 turn to withstand literally anything you throw at him, two if you actually do give him a focus sash.
If you focused statuses, stuff like, healblock, confuse ray/Swagger, will-o-wisp, then make sure you grudged on turn 3, you've got a pretty awesome disabling nova.
Just Spite Spite Grudge would be an interesting combo too.
Alternately, if not in smogonfag rules arena, that's two turns free worth of evasion setup, which shedinja has in spades with both doubleteam and flash.
Heck, it's got protect and endure on it's move list. You wanna see an annoying stall? Right here buddy. And all with just 1 HP.
But still very killable. Which is the point. Sturdy on a Shedinja isn't broken.