Short answer: no
Long Answer: Zapdos / Jirachi are good in Standard because the pool of good consistency cards just aren't there and Jirachi just happens to be the best at it at the moment. Expanded is less "rock-paper-scissors" and is more about meeting a "barrier to entry". This barrier being Zoroark-GX. Can Zapdos / Jirachi beat a Zoroark-GX deck consistently, or at the very least have a 50/50 shot against one?
The glaring problem right off the bat is that Jirachi / Zapdos is LOW HP Pokemon. And not only that, low HP Pokemon that can't stream OHKOs at the drop of a hat. There are two types of decks that can get away with running low HP anything:
- A control variant
- a deck that uses one-Prize Pokemon to stream OHKOs (Night March, Vespiquen, Lost March to anme a few).
Jirachi / Zapdos tends to run with a lot of gas in the beginning, but tends to run out of steam quickly. So you're not going to OHKO Zoroark-GXs or Tag Teams quickly or consistently.
Alolan Muk, Garbotoxin Garbodor, and Silent Lab are more commonplace now. Zoroark-GX / Garbodor is being seen as one of the best, and safest, decks to play in Expanded currently. Can you handle turn-2 Alolan Muk/Garbotoxin? Because as soon as they see Jirachi, they are coming out and you're going to be hard pressed to stop it. You might be able to curb a Muk play (KOing a Ditto Prism Star), you won't be able to stop Garbotoxin before it happens.
Credit where it's due, the deck does boast some good consistency. That said, it's not "I'm going to draw a bunch of cards for free every turn" consistent (Zoroark-GX).
If you really want to run a Team Up deck in the next expanded Regional, either go with Archie's Blastoise or Pikachu & Zekrom-GX...or Zoroark-GX / Garbodor. Those are your tier-1 right now.
Pikachu and Zekrom-GX is going to shake the meta up a bit. Not as much as Magikarp & Wailord-GX did for Dallas. I see P&Z-GX pushing some rogue decks off the edge of the meta and onto the floor (looking at you, Trevenant). Zoroark-GX / Golisopod-GX (winner at Dallas) was a great meta call, but the big fish is now Pikachu & Zekrom-GX.
And don't count on Fighting-type decks, as Pikachu and Zekrom-GX decks will run Flash Energy (removes Weakness). The matchup is a lot closer than you'd think. Buzzwole is getting shaky to run, and it's going to get worse when Unbroken Bonds gets released. If I were to put money on which Figthing decks would see a greater degree of success, I'd put it on Lucario-GX with maybe some Enhanced Hammers.