https://www.techradar.com/news/oneplus-7-could-support-5g-and-be-sold-by-us-carriers

We’re probably going to see the OnePlus 6T before the end of the year, but OnePlus is already looking further ahead and claiming that in 2019 it will launch one of the world’s first 5G phones.

That claim was made by the company’s CEO and founder Pete Lau at Mobile World Congress Shanghai, according to PC Mag, with Lau - who's likely talking about the OnePlus 7 - adding that this is possible thanks to his company’s relationship with Qualcomm.