going by FIBA's list and adding a few notes:

Adem Bona
(2.05m, PF/C, original name: Ikechukwu Stanley Okoro), athletic Nigerian-native wearing Hakeem Olajuwon's jersey number (34), like his role model Giannis Antetokounmpo, seems to have big potential and the thing I see as the most positive sign is his continuous improvement.

Davide Casarin (1.93m) made his Serie A debut and played two games in the Italian Play-Offs. Casarin is also coming off an impressive showing at the FIBA U18 European Championship 2019, where he averaged 8.8 points, 2.5 rebounds, 2.3 assists and 1.5 steals in four games despite being two years younger than the rest of the competition

Lefteris Mantzoukas (2.04m, F) Mantzoukas has already shown he can play with adults, debuting in the Greek top flight at the end of the 2017-18 season - at 14 years of age (see EverGreen's post). Last season he even debuted in the Basketball Champions League for Promitheas Patras.

Nikola Radovanovic (2.02m), Radovanovic is a lefty shooter and scoring machine.