Yes, Nokia 6.1 does support fast charging. During our tests, we have found that it took about 30 minutes to charge the battery from 0% to 50%.
Yes, Nokia 6 (2018) does have the OTG support.
No. Nokia 6.1 (2018) does not have the autofocus in the front camera. It has fixed focus camera as selfie camera.
Yes, New Nokia 6 (2018) does have the series 6000 Aluminium Alloy metal body.
Yes, Nokia 6.1 (2018) does have the headphone jack and USB Type C port also.
At the end of the day, the Nokia 6.1 (2018) brings some welcome improvements over its predecessor.