Metal is a hot-blooded and dedicated shinobi, much like his father Rock Lee, who he has sincere respect for, and his father's sensei. This was depicted when he was seen participating in his father's gruesome training regime.
Metal bears a strong resemblance to his father with his dark eyes, black bowl-style hair cut, and bushy brows. However, his eyes are noticeably sharper. His likeness is further perpetuated by his attire; he wears a green jumpsuit with orange leg and neck warmer and bandages over his hands. In Boruto, he exchanges his neck warmer for a scarf.
Like his father, Metal appears to specialise in taijutsu, and is recognised as a genius within his clan. He's shown great stamina and strength, keeping up with his father's training and capable of holding his own against Shinki, as well as repelling his puppet into a wall with a single kick.
During the day of the Kage Summit in Konoha, Metal was rigorously training with his father. As his father emphatically told him that he was in the springtime of his youth, the young man echoes his father's words, much to his father's approval.
Boruto: Naruto the Movie
Main article: Boruto: Naruto the Movie
Metal Lee takes part in the Chūnin Exams with his team where they pass the first part of the exam that is monitored by Sai Yamanaka, thus leading his team to the next round. Metal's luck runs out during the second part of the exam when his team encounters Team Shinki. While Metal was fighting Shinki, the latter uses his Iron Sand to steal the flag of Metal's team, eliminating them from the exam, much to Metal's disappointment. He later watches the final round of the exam beside Konohamaru Sarutobi.