Without his speed edge, he probably loses round 1 more often than not. His sheer Force power could still very well dominate Malgus (and certainly Lumiya), so he can still win, just with extreme difficulty, but only if he dominates Lumiya first and makes excessive use of Force power.
For round 2, if Sidious destroys Lumiya first, then he wins. If not, he probably loses.
In sabers. If Sidious is using two it will be close but due to numbers I'd say the team just by numbers and it's barely almost a tie.
Normal circumstances Sidious wipes the floor. Kun can't handle Sidious power and Malgus can't contend in saber and with his force power and skill with the blade he can keep lumiya at bay while he stabs Malgus and chokes Kun.