The three players will play in the National First Divison, with Mthethwa joining Richards Bay FC while Khaukanani will play for Tshakhuma Tsha Madzivhandila. Hlongwa will spend the season at Real Kings FC.
Mthethwa, who recently featured for Bafana Bafana in the Cosafa Cup, played for the national Under-20s and is seen a future star of the Buccaneers. With more game-time in the NFD, he could come back and fight for his place at the back.
The Buccaneers, meanwhile, also sent out Tercious Malepe on loan to Ajax Cape Town, who could be looking at replacing Rivaldo Coetzee.
Coetzee has been linked with a move to Mamelodi Sundowns.