This is the only information below, I can offer as to how to add a video to your listing, you may wish to try on a laptop / PC and use Chrome too.
You can only add one video per listing, but you can use the same video on multiple listings - you just need to upload it once.
Upload a video using the new listing tool by selecting Add video from the Photos & Video section: - The video should be .mp4 or .mov with a 150MB limit, or about one minute long -
The new listing tool is currently only available to Seller Hub users https://www.ebay.com/help/selling/listings/creating-managing-listings/add-video-to-listing?id=5272
@mamal-275
