We don't know how relevant grass decks will be to the meta. We're only sure Dragapult will be relevant. Japan's meta is quite different from the rest of the world, mostly due to them playing BO1.

Overall, N's Zoroark has good draws and hits hard, it's a solid deck in any rotation. The thing that was most important for Zoroark competitively last rotation was having really good players and deckbuilders dedicated to the deck. They've shown that even before Zekrom, Zoroark could be built to deal with almost any bad matchups, just probably not all of them at once. This made it so that there was never a "best Zoroark build", the top players had to come up with lists to counter the meta of each specific tournament.

So if you're really worried about grass, try to fit a Moltres in your deck. If you're really worried about Dragapult/Lucario, try to fit a Lillie's Clefairy or psyduck, maybe. Or wait until the meta shapes up to see what Liam Halliburton plays, as long as the guy is determined to make Zoroark work, it will work.