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Chengxi Huang confirmed for the four girls and Inojin + his bird:
Source: https://www.instagram.com/p/BS8RBCBjnS0/

Sarada, Mitsuki & Boruto: I think Tsumagari originally, but Nishio corrected it heavily
Shikadai : unknown but likely Nishio corrections
Metal Lee : Nishio, re-drawn in the BD version, I think it belonged to Koyanagi originally
Iwabe's hammer and debris: Koyanagi
Denki : unknown but maybe Koyanagi