There is a french version ("Les Coulisses D'une Légende") on the fourth CLV side of ROTJ, in the french "pyramid" box set.

The resolution is not that high, but the colors seems correct (better than the many pynkish scenes found on ANH in the same boxset); there are some french subtitles (in yellow, mainly when showing some of the movies scenes) but I bet they are on the screen for less than 5% of the time, and maybe could be erased using the japanese counterpart, if in the same frame there are no japanese subtitles...