OnePlus will launch its first 5G phone in the second quarter, but it won't start in the US
https://phys.org/news/2019-03-oneplus-5g-quarter-wont.html
Unfortunately, that phone won't be launching in the U.S.
The phone, which OnePlus will be showing a prototype of at the Mobile World Congress tradeshow in Barcelona next week, will first launch on United Kingdom carrier EE and Finnish carrier Elisa during the second quarter of the year.