You can't. Those systems are not designed for large video sizes. You can always upload the video to something like Google Drive or Google Photos then send them a link though.
There's two ways to send 4k videos without losing resolution, first option is, is using Samsung Quick share, you'll have to upload your video, then send to the desired contact and then they have 24hrs to open and download the video before the link expires. 2nd option is to use Google message and make sure the other party is using it as well. And you'll be able to send any videos or pics without compressing file to lower quality