There are a lot of poor GW novels, but I've always liked Dan Abnett's 'Gaunts Ghosts' books. They follow an Imperial Guard unit that goes from being a men-only crowd from a forest world to absorbing survivors of other regiments as they are ground down over the years. There are female soldiers, snipers, NCOs, officers etc, and they use the same kit as the guys. Perhaps as the Administratum doesn't give enough of a shit to supply sexy combat lingerie when life expectancy is measured in weeks :D
The Enforcer series stars a female Arbitairtor and is pretty good, all things considered. Now if they would finally make a plastic Sisters of Battle army again...I'm also glad that their Age of Sigmar line is trying to put women front and center. The Stormcast Eternals are unisex unlike the man-only Space Marines. Multiple new female models are being introduced. Many of the surviving characters from the old Warhammer Fantasy are the women characters. It's not perfect (the new Drokath Chieftain model is...meh at best) but it's still a step in the right direction. They also tend to alternate between a good design and a stupid one so at least it's not completely terrible.