Thank you for your precious help. I get good results using your settings. MPV is now my main video player, let's use it for a while.
In fact the motion flow of my projector is way better than SVP so SVP image interpolation won't be active most time, but in some specific cases it will be welcome.
By the way, I used this tool to generate a config file : https://glowmpv.github.io/
This tool made bad video settings so I replaced them by yours, but for the other thing it is rather usefull.