hi homeak, i suggets you UDP connecton, you need create a UDP server on your pc and then send the byte data, not unreal maybe python or what ever you want to send webcam data throw that socket, and on your android you can receive things, getting the byte data with a FSocket* client and then transform to texture2d*
here, this a wiki with UDP connection [New Wiki] UDP Sockets, Sending / Receiving any custom data from 1 UE4 instance to another - C++ Gameplay Programming - Unreal Engine Forums
and here is a wiki to create dynamic textures: A new, community-hosted Unreal Engine Wiki - Announcements and Releases - Unreal Engine Forums
if you dont have experience with socket and you dont know about RHI system you need read a lot!
cheers!