Hi,
No, there is no way to do it. HTML5 video element has the "preload" attribute just for indicate if you wan to preload the all video or just the metadata, but never streams the video as you are suggesting.
To stream the video, you need to use HLS or MPEG-DASH. HLS is supported by the videoplayer plugin (as far as I know), but you could find some limitations on iOS.
Have a look to the manual: https://krpano.com/plugins/videoplayer/#videourl
Cheers