Never was it stated in the manga that your chakra increases with the ms or ems, dunno why people keep making up suck nonsense.
Anyway chakra automatically increases as you get older and decrease when you reach a certain age. Chakra capacity might get stunned for various reasons though. Anyway sasuke is getting to the age where his chakra will automatically increase and i wouldnt be surprised if when the new databook comes out his chakra has increased no different to part 1 and part 2.
Also im certain the ems allows the user to use its techniques which minimum chakra consumed and defects on the body