Re. the alleged "ground forces" ahem, "uniform" from DS9: Nor the Battle to the Strong
It's worth taking a careful look at either the original episode or the screen caps on somewhere like trekcore.com
as this actually shows the costume to be just the standard Starfleet costume at that time - i.e. A black jumpsuit with branch-colored shoulders and grey undershirt (albeit suitably "distressed" in appearance...!) - over which is worn the padded black jacket with branch colored trim below a black yoke.