The OnePlus 3 and 3T may have launched with Android Marshmallow in 2016 and received Android 9.0 Pie earlier this year, but both can now be upgraded to Android 10. The Qualcomm Snapdragon 820 and 6 GB of RAM, or Snapdragon 821 in the case of the OnePlus 3T, should be well suited to run Google's latest version of Android too.
https://www.notebookcheck.net/The-OnePlus-3-and-3T-can-now-be-upgraded-to-Android-10.440341.0.html