I've not used Scaleway but for what it's worth Digital Ocean's snapshot feature only works offline too (and takes forever to run). I'd also made the same complaints as yourself that an offline "snapshot" isn't really what I would class as a "snapshot". A "clone" would be a more apt description.

Anyhow, semantics aside, I seriously wouldn't recommend DO for any serious work. It's fine if you freelance in Wordpress or other off the shelf products but if you have any serious work to do then just don't even waste your time with DO as it's solutions are slow, inflexible and, in my professional opinion, immature when compared to other leading cloud providers.