Brother in Christ, it's the exact same for me. I learn Sylethi (a dialect of Bengali), its my mother tongue. I know bengali as well, with Hindi, English and Arabic (need to read the Quran yk). I mostly stutter in Arabic cause of the pronunciations, I sometimes stutters in Hindi and English, and none in Bengali or Sylethi (if I ain't around the huzz). Arabic pronunciation are too complex fr. English has the most simplest words and pronunciation. Bengali,Sylethi and Hindi are not as complex in pronunciation in Arabic but definitely not more easy than English. Am 16m, just hoping the stutters goes away, shit's awful. May you help with your stuttering too.