Ones I know for sure in the Dts:X format on Bluray are (at least in the UK)
Fast and Furious 8
Crimson Peak
Atomic Blonde
Jason Bourne (5th film)
Pitch Perfect 3 (not really much improved over just the Dts HD MA although there are moments)
On the whole the majority of either the Atmos and Dts:X films from the last couple of years are worth a listen/watch. The numbers of Atmos greatly exceed that of the Dts:X or Auro 3D. Anything earlier than,
I think we agree, 2013 then it was not originally done in the Cinema as either Atmos or Dts:X and so the discs are likely just an up mix if they claim Atmos/Dts:X. Most,
but not all UHD discs have either Atmos or Dts:X although occasionally it has both. America/Region A has a lot more Atmos/Dts:X bluray examples than Europe/Region B or Asia/Region C. Auro 3D are few an far between although I think there are a few examples from Germany.
All UHD discs are I think region free, although their additional bluray discs can be region locked.
Picking favorites is a little bit cruel as most have something to recommend them.
However...
Ready Player One (The opening track race)
Mad Max Fury Road (Pretty much the whole first 30 minutes)
Hacksaw Ridge (The whole battle scene)
and the list would go a fair bit. (The first page list is by no means definitive)
Even up mixing can and does work well for Dvds and Blurays. Pretty much anything from the last 20 years would most likely improve.