After seeing off Angola on Tuesday, Banyana hit the ground running as early as the second minute through a long-range shot from the far side of the area by Mapula Kgaole.
An opportunity for a second goal ten minutes at the midway stage in the first half came from a one-on-one by Kgaole, who wasn't able to beat Eswatini goalkeeper Nokwanda Mamba.
Sibulele Holweni put the host nation at ease seven minutes to halftime after leaping high on the near side of the area to steer a delicate cross from the righ side past Mamba.
Three straight substitutions from Banyana after halftime saw Nonhlanhla Mthandi, Xiluva Tshabalala and Oratile Mokwena enter the pitch.
The number of changes did not affect the side's rhythm, Banyana bagge the third goal two minutes into the second half when Gabriela Salgado cut into the area from the right to rifle into the near side of Mamba's net.
Desiree Ellis' side continued to dominate after 52 minutes as a poor touch from Eswatini at the back let Holweni in on goal, but Mamba rushed off the line to keep out the threat.
Banyana marched eve further ahead seven minutes later as a curling shot from afar by Kgaole caught Mamba napping before rattling the net.
Banyana rounded off the scoring with the last kick of the game through a cracking free-kick from Salgado, as Ellis' troops advance to the final four.
