That is a wonderful video. The gibberish she speaks in Each language sounds pretty convincing, although I noticed my relationship with each language affected how it sounded a lot.

French and Spanish: I've heard them around but never spoken them. She sounded perfect.

Swedish: I used to be able to speak it but have forgotten. She sounded even more convincing than in French.

Japanese: I speak it now but not natively. She sounded pretty rough and not all that Japanese to me.

English: My native language. My brain tried so hard to make sense of it and pulled out snippets of words but there was no grammar there.