There are lots of ways to do this other than flipbook.
I saw one recently in Mathew Wadstein’s unreal online learning course about pixel streaming.
He doesn’t talk about it in the tutorial but in the downloadable UE4 project included in the course, he has a Media Player asset and a media texture which plays a sequence of png files at 30 fps. I thought it was a video but I found it was actually just a really fast slideshow.