Xenan Elves [Masters]

Used this deck to climb from Diamond III to Masters right after the release of the new expansion. ( https://imgur.com/a/x1WYFl1 - last history of games. Didn't capture all of them, but got the achievement for winning 10 games in a row before with this deck. It's quite strong and I had a great success with it)
In the previous season I used a similar deck, but now we lost cards like Tasbu, the Forbidden, Vishni, Lethrai Highblood, Ebon Dune Smuggler
However, with the new expansion and the new expedition we got some interesting replacements and additions.
Feartracker - good in a late game, can save us some life against aggro decks and still can be useful for attacks after becoming corrupted if we have the relic or Tavia on board.
Gravewatch Ancestor - not the best card, but decent 3-drop with actually good ultimate for a late game.
Banish - new addition to the Expedition format. Really powerful removal tool. Also quite relevant against some relic based decks.
Defile - very good in a early game, also can buff our Bloodseeker later.

Overall the strategy is very simple:
Play early drops ( Bloodseeker, Borderlands Lookout, Lethrai Ranger, etc );
Use Tavia, Lethrai Raidleader and Sunset Stone to buff your elves;
Use your removals to break through opponents units.

We have some decent late game by using Sunset Stone's ability, playing Feartracker and Incarnus, Makkar's Listener and using Gravewatch Ancestor's ability.

I don't think that this is a perfect final build. I still haven't tested Damara, Deft Saboteur (although not sure if she fits this deck in Expedition). Also didn't have a lot of problems with powerbase, but maybe there is still something to improve.

I hope this deck can help you. I do think that Xenan is quite strong in Expedition right now.
If you have any questions, ask in comments.