Does the Nokia Lumia 1520 support otg pen drive?

nokia lumia 1520

No. Never.

I wouldn't say never, what facts have you for this?

But no Windows Phones have OTG at the present.

Posted via the Windows Central App for Android

It's quite possible it may happen in the future.

but for now, and for the near future, the answer is no.

but can the current flagships supports by some future software updates???

Technologically, yes.

However whether it will actually happen, I will wait until Windows 10 Mobile drops to see if existing devices get the feature.

It is SoC dependant.... And possibly depends as well on if the SoC has the correct connections. TL;DR

Then it needs the firmware implementation.