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yt-dlp should still be the best option. When it comes to unsupported websites you usually need to add some options. Most of the time this is just --referer https://example.com/ with the website being the one this is hosted on.
There was a discussion about something similar some month ago here. Where I made a more detailed comment.
(You could DM me more details (like the catoon site and the cartoon you want to download) and I could look into it more closely.)
For content from streaming platforms like Netflix, the audio and video lines up most of the time. The dub might be a bit longer at the end, but that doesn’t matter; it’s only the credits.
For Blu-ray and DVDs, it’s a bigger problem. The audio and video lines don’t usually line up: different production company logos of different lengths and maybe minor regional differences. You could probably adjust the audio delay in the video player to get a decent experience.
mpv is good video player where it is easily possible to play the video from one file and the audio from another.
You can just fork it and replace the image.
The authors talks about it here on their blog a bit more.