Depends on how far they go in the playoffs this year, if they're a first round exit, he maybe explores being moved in the summer, if they go at least to the WCF or Finals, I can see him staying in Vancouver. That's a tough cap hit to handle at 12-13m or whatever he's projected to go after. It's one of those things, if they move him at the TDL, they risk losing the edge in scoring heading into the playoffs, but if there's a deal that adds some incredible pieces and opens up cap to say...the JR/Allvin special of ex-Pens and Guentzel is on their radar with cap space, they could be just fine and add enough scoring depth to be better.
That left side is pretty rough and if they can move Pettersson to add a top 6 winger and a young prospect, with Elias being RFA, it gives a team some flexibility but I believe because he's RFA, to get the 8yr deal he'd have to do a sign+trade (like Tkachuk with Flames situation) or whatever that rule is.
This is a team like Arizona can offer whatever they want, they'd probably want to see if they can re-sign him and there's zero chance Elias will want to sign there even at league max.
As a Pens fan, I'd happily do Rust + Guentzel for Pettersson, pending Rust & Guentzel's injury updates and what not, but that would be contingent on Jake wanting to re-sign in Vancouver. There could be incentives for him to do that there, familiar with the management and coaching staff, his close friend Boeser is there and they're both repped by the same agent. Rust and Jake add serious playoff pedigree as well, also coach familiarity.
Rust is hanging back in Pittsburgh but Jake is travelling with the Penguins on the 4 game road trip, which is curious.