I wouldn't say Tuch or Lindholm are underperforming, moreso last season was an outlier for them.

EK65 was 99% of the Sharks’ schemes, he’s not in PIT
Lindholm deal was optimistic
Mercer is in the common 2nd season woes
Wasn’t Kuzy shooting % super high last season? (Idk)

JRob, Tkachuk, Thompson, Terry aren’t huge worries but not something to be calm about

Gaudreau picked the worst team to go to

Robertson: Dallas is just stacked all around, don’t really need him scoring at a 100 point pace
Thompson: The sabres in general (minus Dahlin) have been struggling
Tkachuk: He doesn’t need to carry the Panthers by himself anymore
Gaudreau: Age and the classic case of someone getting a big pay day after a career year
Dubois: Just not getting played
Tuch: See above
Ovechkin: Age finally caught up to him
Cozens: See above
Debrusk: Ice time got cut
Huberdeau: Just hasn’t fit in with Calgary
Mercer: Same case as the sabres, the devils have oddly been off
Terry: Hasn’t had consistent linemates
Lindholm: One season wonder
Karlsson: Fall off was expected
Sandin: Buried on the third pairing
Grezlyck: Not really offensive minded
Barrie: Not playing
Kuzmenko: Ice time has dropped a ton
Wheeler and Oshie: Old

Without looking I’m guessing that they all have shooting percentages 4-5% below their career averages and on ice shooting percentages low as well.

EK65 may have fallen off points wise but his underlying stats are fantastic and hes actually been really good defensively so far

Karlsson started the year nearly point per game and was looking amazing. Haven't seen too many recent games but I'd assume he's slumping with the team.

But i have seen several posts that him and Petterson have been a REALLY good pair and have great numbers

Wheeler is just washed. Can’t really skate and just turns the puck over a lot. Occasionally makes a good pass or two

Have to think he’s not in the lineup come playoff time