[Update 31/Oct/2023: you can see a new version of this deck, Dark-Thing Lad, that takes into consideration Angela recent nerf and my personal adquisition of Iron Lad]
This deck has been working perfectly for me the last 24 hours. I was in rank +10000 and now I'm between 1000-2000 (and still going up). It has managed to beat many current meta decks with not much effort.
You may wonder why White Queen. First I had there Shuri (I know, non-sense with this deck, I just came from a Shuri deck and thought it didn't hurt having Zabu, but it did...). With Shuri the deck had a winrate of 55% at best, I change her for White Queen because it seemed as an interesting candidate to be lowered in cost by Zabu, good cost/power relation, and just changing that it became a 80% winning rate deck for quite a while (with time and harder contenders it come to sort of 70%, and also the winning rate you see is a mix of this deck and the one with Shuri, that's why appears a little lower in stats if you read it very close to publication). I think the main reason White Queen helps is the amount of information it gives you about your rival's last turn, so your Shang-Chi and Shadow King will work better. It also could give you an useful counter if the card is good for your game too, and if it doesn't work in any of those ways still a 4/6 potential 3/6 to play. I don't have Iron Lad and that was actually a card I guess I would have put instead of White Queen if I could, so I think it's something you could try if you like.
Captain Marvel is another important card, specially in current meta with a very present Alioth (good she's +1 over Alioth now if it was a close in power location you were winning or in tie), sometimes she will be there to take the place you couldn't play, maybe with the help of your Jeff, also helping both to win unplayable locations. It also was a huge help with Rickety Bridge, if you have it in your hand and see Rickety Bridge you can almost inmediately Snap, you likely win that location (play any card with at least 1 value there on last turn or move your Jeff there). If your rival doesn't play anything you win for the card you used, if he does you both lose the location and Captain Marvel comes to the rescue. If your rival plays Armor it works too (she will go there too and has +1 power over Armor), if he plays Colossus too (your card will die, but she will go and is +1 over him). Only strategy that would win you is your rival playing there last turn a Bucky (so be aware in case they're running Destroy and still haven't played a Bucky).
If possible, prefered order of play would be Zabu (as soon as possible), and then let always for last turn Shadow King + Shang-Chi (usually played at different lanes). At worst, you can play them on turn 5 (6 if Limbo) if you think you won't have the chance at the end or are afraid of some counter. You can also try letting Cage and Darkhawk as last as possible, to avoid Rogue/Enchantress. That depends on how you see the match developping.
Also, Zabu serves two purposes: many will go for him soon with their Rogue (so there will be no counter for Cage and Darkhawk) or even Enchantress.