Might be tricky to find, so if you want user replaceable batteries in a Mouse, maybe get a USB AA/AAA battery charger and use any of the many mice with AA (Or AAA) batteries. Recharge the batteries by plugging in the USB charger when they get low ?

My Logitech MX Master 3S is USB c rechargabke but not user replaceable batteries

@BarHocker There are likely still mice using standard AAA batteries out there.

Unfortunately, the mouse is only sold in a keyboard/mouse bundle, but the "CHERRY STREAM DESKTOP RECHARGE" bundle might be something you would be interested in. Both keyboard and mouse have replaceable batteries and these suckers are built to last. The mouse is little bigger, so def. have something in your hand and it has super silent buttons. I especially like the type-feel of the keyboard. I am normally totally I to mechanical keyboards, but I can totally tolerate typing on it. 😉

Edit: Oh, and I forgot. You can recharge them with a USB-C cable.

(Disclaimer: I work for Cherry, but IMHO it is still a very good product for the price. )

Logitech G305. No cord but has a replaceable AA battery.

You're not going to get both a replaceable battery and a rechargeable mouse with charging cord.

You can get rechargable AA batteries that actually have a port on them. But you need to remove it to charge. Just keep a spare in your laptop bag

It's reasonably easy to replace the internal battery of many mice, which might be worth a try if your mouse is fine otherwise.

E.g. below is an example of a Logitech G Pro Wireless battery replacement. These exact tools aren't necessary, and a replacement battery can be found for 10-20€.

https://www.ifixit.com/Guide/Logitech+G+PRO+Wireless+Battery+Replacement/145490