When creating a Hololink with video, 3D models, images and audio of your own, simply upload them to the scene in one of two ways.

Simply open one of the asset libraries, and click the upload button. Then choose the 3D model, image, video or audio-file that you want to upload and it will be uploaded to your team library and be immediately available in the scene you are editing.

Check out this article to see which file formats you can use: https://intercom.help/hololink/en/articles/5161534-file-formats