Notes: Mebachi credited herself in the video description as" 絵", "drawing". It does not refer to animation whatsoever but to the cover of the single with the song you hear in the PV (http://maltinerecords.cs8.biz/155.html).
作　謎のアニメ団 in the other hand feels a very very generic way to collectively credit multiple members of the Nazoani group but there is also to consider the fact that no actual member of the brigade was confirmed in the past so it can also simply be a mean to credit Yoshinari alone without give his identity out, ruining the magic of the "misterious" group. However to me the second and third cut very thick, brushstroke-like, outlines and eyes feel very much more Mebachi to me than any of the Mebachi imitations made by Yoshinari in the past.

i agree those two cuts look like her own illustrations, and the same digital brush for lineart she usually uses in them. everything else looks like yoshinari, though

edit: did a bit of digging, those cuts are hers https://twitter.com/nazoani02yume/status/1160220185439031296