We shoot Glock 17/22/27 and M&P 40/45 (full size). Wife (5'6") is very proficient with G22 and carries G27 with +1 Pearce Grip mag extension.
Although she is a Glock fan (she gets smallest/fastest shot groups at 7/10 yards with them compared to many other semi-autos she shot), she really likes the small grip inserts in the M&P which fits her hands like a glove and prefers the more ergonomic mag release and slide release. It took her some getting used to operate Glock's mag and slide release but was able to operate M&P controls without any issues the first time she picked them up.
M&P 40/45 recoil is less and my sister (5'4") and wife both commented it is "softer" recoiling than G22. When my sister wanted to upgrade from her .380 Makarov for HD, she shot all the pistols we have in 9mm/40S&W/45ACP. Her pick was M&P40 over the G17 which I thought she would prefer. She said the M&P40 recoil was just a bit more than G17 and she preferred the larger caliber bullet.
After I did a
trigger job on M&P45, I found my wife shooting it more and more. 200 gr SWC with 4.0 of Promo is her favored plinking load that she shoots accurate with mild recoil, but she is now shooting 200 gr SWC with 5.0 gr of W231/HP-38 very comfortably.
In the years past, I have endorsed G17/19/26 for female shooters but now I just have them handle and shoot all the pistols first and let them make the selection based on comfort, ease of use, accuracy/speed of shot groups they attain with each pistol. I was surprised when my 5'4"/Size 2 sister chose M&P40 over G17 based on fit to her hands, ergonomics, and recoil (she actually shot the M&P40 much more accurate/faster than her .380 Makarov she has shot the past 15 years).
Have your wife handle both and range test them. Field testing will give your wife first hand assessment of how each pistol handles and shoots while keeping your comments/preferences quiet. Holes on target and how fast/comfortably your wife can shoot them should dictate the final selection.