Can the owner change Youtube video license after someone used the video?
For example I used a cc video to make a video. Then the creator made it to standard youtube license. So will i get copyright strike for that?
Creative Commons licenses are perpetual. Once a work has been licensed under a Creative Commons license, the authors cannot revoke that license.
However, users on YouTube can change the license displayed under the video. Legally, you are in the clear, since the video you had downloaded was licensed under Creative Commons. However, if you get sued, you may need to prove that the Creative Commons license was there at one point.
I don't know how YouTube handles this, and whether they keep track of the history of licensing information when they handle copyright disputes. YouTube is not obligated to keep any video up. They can choose to take down any video they like, even if the video doesn't break copyright.
Yes you can. Here is a screenshot of where you can change it. When you go into the YouTube studio, and click to edit your video details, Its under, License and distribution: