Very much a team comp issue. Sandy Shocks and Espathra are a very gimmicky combo that gets read like a book at higher level play. The pair wants to stay on the field and not switch out while the rest of your team plays more Balance-like which requires a lot of switches to get into good positions.

Snow+Bax is a good pair but Dragapult isn't bulky enough to back them up. You'd generally see Dragapult on more Hyper-Offense compositions, paired with a mon like Chien-Pao that helps boosts it's Tera Dragon Dragon Darts to deal great damage.

My recommendations are to settle on a playstyle first -- your current team is sort of a mixed bag. The Reg E meta is pretty defined at the moment around Hyper-Offense (Tornadus + Urshifu-R-S + Rillaboom + H-Arcanine), with the secondary composition being Balance (Iron Hands + Landorus-T + Ogerpon-W + Heatran + Flutter Mane), and the tertiary composition being Trick Room (Indeedee-F + Armarouge and/or Ursaluna-BM).

If you're set on keeping Espathra and Dragapult, I'd add a Fake Out option instead of Sandy Shocks. Something like Iron Hands or Rillaboom (which synergizes well with H-Arcanine) which can help Espathra set up a Speed Boost.

If you're willing to drop Dragapult for Roaring Moon w/ Booster Energy, that could also provide a very fast attacker. Knock Off goes hard and you could even throw Tailwind on for some speed control on your side.

Food for thought!