Examples of how a couple of sites block YouTube videos until users give cookie consent.
Another option is to embed Youtube videos using "nocookie" in the url (e.g. www.youtube-nocookie.com/embed/Sno5o_20adQ).
University of Edinburgh
Example of cookie acknowledgement covering a video
Link to the page where the video is placed: www.ed.ac.uk/about/annual-review/1213/video
European Data Protection Supervisor
Example of a cookie notification covering a video
Link to the page where the video is placed: edps.europa.eu/press-publications/press-news/videos/25-may-2018-gdpr-day-key-word-accountability_en
Replacing the video with a youtube image until the user accepts the use of cookies.