is it possible to upload OBB file on any server and then download that when game is launched
No, it is something must be at GooglePlay side, if you've time to go through this from Google Android Documentations:
If you don't, then it is basically says at one part:
So basically, all points to the fact that those files is basically uploaded tot he store itself. And you will not find any post showing you a method where you can provide an external URL.
And anyways, this is a great forum post to help you to deal with the OBB stuff: https://forums.unrealengine.com/showthread.php?50680-*Please-sticky-when-finished*-Unreal-Engine-4-with-Android-HOW-TO-%28With-OBB%29
answered Sep 25 '16 at 03:35 PM
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