Question about renting an airbnb property for reception

Airbnb no longer allows events at any of their properties, it's a policy.

Have you looked at a restaurant with a private room as a location? You can have your ceremony there and then just go right into dinner. You should be able to find one within your budget as long as you aren't looking for a special occasion venue with all of the extras.

They may change their policy, but who knows. Anything and everything is very expensive in Sonoma county. If you drive about an hour further everything is way cheaper. What is your budget for your venue?

You shouldn't plan around something that isn't allowed, I also don't think they'll change their policy either. You could cut your guest list in half and likely find a giant AirBnB that will accommodate everyone, but I suspect that will be very expensive in wine country. If you were to go this route, I also would not assume your guests would want to contribute to the cost (not sure if you were planning on that, I've seen others post something similar) as a guest you want to choose your hotel when you're paying so much.

Well, some people are willing to travel to destination weddings for, say, a 5-hour reception. So this really isn't that different as long as you are having a ceremony (no matter how short) that they can witness and hosting a celebratory meal. It's expensive for guests to pay for travel and accommodations, yes, but that's the common downside of destination weddings. Your guests should feel free to decline if it's not within their budget.

I would be really careful, though, not to downplay your Sonoma ceremony in favor of your French one to your guests. It's fine if you feel the one in France is more important, but I would keep that to yourself.

Also, even before AirBnB made this change, I looked into doing this for my wedding and realized what a costly mess it would be. It may seem like money is being saved but you have to purchase or rent everything - chairs, table cloths, food, lights, everything... plus, you'd probably need to get professional cleaners or spend a full day after your wedding cleaning. All of it adds up to a lot. I'd just look into a normal venue.