I found a fantastic Youtuber with the super secret nickname of Kemushichan. Outside of the super secret spy nickname world that is Youtube, Loretta is the name of this amazing 19 year old (according to her Youtube profile). She speaks English, Japanese and Mandarin. I cannot vouch for her Mandarin, but her Japanese is great. Not only that, but her videos are well edited and fun.
She started a series of videos for discussing challenges faced while learning Japanese. (日本語の難しさ nihongo no muzukashisa) I haven’t watched all her videos yet, but I particularly liked this one on multilingualism:
She only has 392 subscribers (I happen to know I was the 392th). Subscribe!