Yes, BlackBerry KEY2 does have the OTG support.
Yes, BlackBerry KEY2 is VoLTE enabled mobile phone.
Yes, BlackBerry KEY2 does have Qualcomm Quick Charge 3.0 support. It charges the battery from 0% to 47% in just about 30 minutes.
BlackBerry KEY2 has a USB Type-C port.
BlackBerry KEY2 is available in 2 variants - Single sim and Dual Sim. The model available on OnlyMobiles.com is a dual sim variant. It has a hybrid sim slot. You can use either 2 sim cards or 1 sim card and a memory card.
Stellar battery life. A tactile and genuinely useful keyboard. Great software with a focus on security and privacy. What more could you want? The BlackBerry Key2 is an exceptional phone.
The BlackBerry KEY2 is the best Android-powered BlackBerry ever made, and it improves on last year's formula in almost every way.