I loved Arcanum and this looks to be that times 100.
Personally I don't think Divinity will ever quite live up to Arcanum but they're both pretty different games. To OP, is this an Arcanum sequel? No, not in the slightest. You can very broadly paint them similar enough but you'd just end up lumping the majority of cRPGs in there too. For instance, Tides of Numenera does everything you exampled.
Ultimately though it'll feel similar enough that I think you'll enjoy Divinity Original Sin 2.