I would highly recommend the Alien Gear Shape shift kit. It’s $100, but you get a holster you can move around and try a lot of different positions. It’s also very comfortable, and it has the same retention as a kydex holster (you get a “click” and know the gun is holstered). You can also buy part of the kit from them if $100 is too steep. This holster also doesn’t have screws you have to worry about coming loose.
This CYA holster is my favorite. It’s really easy to clip on and go. I have two of these and they have been really good. The screws started to work their way out of one and it made the holster loose, but I put a little loctite on them and I’m good now (most holsters do this).
CYA Supply Co. Fits S&W M&P 380 Shield EZ Inside Waistband Holster Concealed Carry IWB Veteran Owned Company Amazon.com
You want a holster specifically made for your gun. I would get kydex. They do make hybrid holsters with leather and kydex. The Alien gear functions like this, but instead of leather it’s neoprene and the holster part works like a typical kydex holster (like I said earlier). I do have a crossbreed hybrid holster. I like it, but I’ve had more issues with screws, figuring retention out. Good holsters though.