The Portuguese forward only arrived in Yorkshire during the summer transfer window, but he has made a very positive impression at the club.
Although he has generally played second-fiddle Atdhe Nuhiu, the powerful forward has still shown his ability when given a chance, and Beagrie has been very impressed by him.
"He's been tremendous," the pundit said on Sky Sports. "He has the pace, the athleticism and he's clever. He times his runs. He's not caught offside very often.
"He offers a threat in behind, and that can create a hole which the likes of [Fernando] Forestieri, [Kieran] Lee and [Ross] Wallace can exploit."
Joao was handed a start for Wednesday against Hull, and he put in a stunning performance, where he battered the Tigers' defence.
The 22-year-old is still a raw talent, but his power and pace caused Hull no end of troubles, even though the Owls weren't able to pick up a win in the tie.
Wednesday and Hull drew 1-1 on Saturday, in a high-quality game of Championship football, which ensures that they both remain in the upper echelons of the table.
Carlos Carvalhal's side are currently occupying ninth spot in the second tier, while Hull are seventh.