I upgraded to the honor 90 in August, and I have been told that it can get 5g, and it shows that 5g is preferred network but I've never seen it on my phone. Plymouth, Exeter, Taunton all with 5g but I've never seen it on my phone. Salesperson said phone is set up correctly.
I'm sat in my livingroom in Teesside and I have Vodafone 5G. But I'll be out and about tomorrow around County Durham and it is quite likely at some point I'll only get 2G (yes it'll still be there even after 3G has gone). It just depends on where you are. If you want to check there are phone apps out there that will detect 5G.