>>1875813As a French person, it literally never occured to me to pronounce "chan" as it would be pronounced if it were a French word. We would pronounce a borrowed English word like it would be in English without changing its spelling to accomodate French phonetic rules, so why do something different for a borrowed Japanese word?
Besides, if you wanted to respect French phonetic rules, it should be written "tchane" to get the correct pronounciation.