You can get a brand new Shield plus for under $400.00 ,it is one of the smallest hi cap 9mm pistols available. It is 100% reliable with all SD ammo. It fits people with small hands very well. It has a proven track record, and a great warrantee. One of the best if not the best compact hi cap 9mm pistol made.  Have her go to a range and shoot one and see for herself. FYI if you buy one on the net and have it transferred to an FFL near you ,you can save about $50.00 overall over a gun store.

If she is not going to shoot regularly get her a revolver.
Harder to have a ND and much simpler to operate, no Tap, Rack, Bang clearance drills to master, just pull the trigger for a new round.

If someone's not going to train, don't get a firearm. It's like if you're going to get a car, no way around having to learn the rules of the road.

Unless she puts in the work to get proficient with it, any handgun is a disaster waiting to happen, and ineffective at best.

I have no experience with most of these suggestions, but these are the kinds of things I would be looking at:

https://www.ar15.com/forums/Armory/New-offering-from-Ruger-LC-carbine-in-5-7x28/48-538018/?page=1
https://ruger.com/products/lcCarbine/models.html

https://www.guns.com/news/2023/02/28/new-smith-wesson-9mm-m-and-p-fpc-folding-carbine

https://ruger.com/products/pcCarbine/models.html
I have an original Ruger PC9, the newer ones are the same basic mechanism, it shoots fine and completely reliable.

The mag-in-grip designs are a little smaller in overall length for easier handling indoors.

The point is that she's vastly more likely to be able to hit a target with a long gun than a handgun without sufficient practice/training. Get a little red dot with shake-awake and it's point and click with any of those.

If she's willing to put in some range time and wants to pursue carry, then look at a carry pistol. For a compact carry pistol the shoots like a full size I'd take a look at the often-overlooked Walther PPS which is genuinely an excellent pistol in a single stack 9. Wish they made a "PPS Plus" double stack. If she's not necessarily looking to carry, then a larger pistol like the already mentioned Dagger or M&P types would probably be better. HK VP9 is a little higher cost but the little grippy things do make it easier to operate the slide, and the paddle magazine release is superior. VP9SK would make a reasonable shooting medium size pistol that's readily purse carryable.

Don't believe everything you read.  There are plenty of people who haven't had any problems with them.  In the start they shipped with bad magazines and they wouldn't run 5 rounds without malfunctioning.  Most people just claimed they were junk without contacting the company and the reputation was born.  Had people contacted SCCY about the problem, SCCY would have sent them new magazines.  With the new magazines my gun has been perfectly reliable.

I will say they aren't good choices for new shooters because of the heavy DA trigger.  The striker fire version is probably a better choice but they are usually impossible to find.  

My next subcompact "affordable" gun will be a Canik Mete MC9.  It's small enough for purse carry when she needs to and is very reliable, has very good capacity, a good trigger and is red dot ready all at a sub $500 price.

Shield Plus
Factory 10, 13, and 15 rounders

Definitely not a Glock, as they feel unnatural in the hand for beginners ( even in the hands of experienced shooters as well). I have several Glocks and shoot them well, but their is better handguns out there. I always recommend the Shield plus, as it way more beginner friendly and actually quite soft to shoot!

Agree a 100 percent!