Do bear in mind that the Samsung Galaxy A9 Pro (which has been benchmarked on AnTuTu already) has not yet been announced as a device, but the FCC filing has shown us more information concerning the presence of a removable battery through the certification label placement. After all, the physical paper label will be glued on the inside of the battery compartment, and that more or less gives the game away.
Perhaps this is why the Pro model of the Galaxy A9 is a wee bit heavier (to the tune of 10 grams) compared to the vanilla Galaxy A9 that was released in China at the end of last year. Not only that, the presence of a removable battery would also make the handset thicker by 0.5mm – negligible by all standards, actually.