wine cellar chalet, it is insta loss for me as defender

[Tuco]

How do you even win this ?? One emp + thermite + smoke + plant = gg

[Bandit]

Bandit/Kaid Tricking, Warden, or get good

[Joe]

A Maestro works too sometimes against people who plant. Or use Smoke. Throw Smoke in their smoke and see how they like it.

[Mewsha]

Tell your team to stick near the site.

If they're not going to, then it's just one of those rooms where you auto lose.

[AtomicFinjaMaster]

Bandit tricking like, well, Bandit said, is a great option for keeping them out of the garage door, Tubarao can slow the push down as well. If they do make it through, there's a window on the stairs just above it you can peek attackers from. Area-denial ops, like Smoke and even Tachanka can slow them down. You can C4 the smoke once they start going for a plant. You can also set up a Mira on the reinforced wall opposite the garage door, and put a rotate on the right (from Mira's pov) to let you peak easily. Warden and Maestro can work as others have said.

None of these are 100% effective, but it makes the site much easier to defend.