Im looking at an imported Poco F2. It uses bands 78/79, so I do not expect it to work, although unsure about vodafone, but I think it will work in Europe where family is.

The whole 5g bands are confusing to me as this table lists Spark and Vodafone as band NR78 ?

Anyway, my main concern is, will a dual sim model still work in 4g mode? to be honest I dont use mobile data often, just to check emails, locations etc, I find 3g plenty fast enough for my needs and more often than not Im in range of a wifi spot, so it doesnt concern me if the 5g doesnt work, but just wanted to clarify N78 is listed as 3500mhz which I thought was what NZ is using?

https://en.wikipedia.org/wiki/List_of_5G_NR_networks