I have seen the same figures painted with the short blue jacket, but that jut didn't seem right for circa 1900.
As I said, there was a short blue jacket worn during this period, the
veste, but it usually only crops up in photos of non-combat situations, as it was part of walking-out dress. So those skirmishing figures are much more likely to be wearing the blouse.
There's a very cool photo of two drunken legionnaires in Algeria, arm-in-arm, cigarettes hanging out of their mouths and mugging for the camera, being escorted back to base by military police. They are wearing the blue veste, waist sash and red trousers.