>>6229757Here's a Baselard of each type for comparison. Baselard is unique in that she directly reuses parts from her progenitor, with the exact same shield rifles and shoulder parts. You can take the adaptor pieces from her shoulders and attach them to the original Baselard if you like. Most of the time FA Girl parts are smaller and slimmer than the FA parts they're based on, but the kits are of largely comparable height: it's the amount of bulk that differs between them.
The primary difference when it comes to handheld equipment is that regular Frame Arms have hard plastic hands with large rectangular slots for weapons, like HG Gundam models do, while FA Girls have much smaller hands made of soft plastic. Most weapons will fit both hand types, but it may require some work to get certain weapons to fit in the smaller hand type. Both come with compatible 3mm ports and are designed with augmentation via Modeling Support Goods kits in mind.
In this picture, FA Baselard is wearing the Extend Arms 02 set designed for it, along with the tanks from a Propellant Tank Square and the beam sabers from a Saber & Hammer set, while FA Girl Baselard is wearing two Exceed Binders attached to her skirt by the male-male pegs from an Energy Shield that I was using elsewhere. The sword she's carrying is a Mega Slash Edge, with the handle being a spare that comes from a Unite Sword.