TPM Maul/Jaina Solo vs. Ulic Qel-Droma/Exar Kun (lightsabers only)

*Lightsabers only

Round 1: Ulic vs. Maul, Jaina vs. Exar

Round 2: Kun vs. Maul, Jaina vs. Ulic

Battle takes place on neutral ground

R1: Maul slightly, Exar slightly.
R2: Either way, either way.

Essentially Maul >/= Exar > Ulic = Jaina

They're all very close as swordmasters but if I was forced to rank them that would be my answer.

Sith Brotherhood wins both.