Razer Kishi. That’s what I have — but mine only supports Android (I have one of each). It’s USB-C, but doesn’t support my iPhone 16 Pro Max. That being said, if your controller is recognised by iOS, it should work. I use the 8bitdo controller that looks like a Super NES controller, only it has analogue sticks and a second set of triggers (like a PlayStation controller). Works great.

But yes, since Apple revamped the Files app, every app that exposes its files to iTunes/macOS should have its files accessible right in Files, and you can move from the app folder to the download folder and vice-versa. It still isn’t as open as Android, but functionally, it’s just as good. I have no problem moving files between my iPhone and either my Android phone, or my wife’s. What you really need for this is an app that will set up a file host, and that app also needs to expose its files to the Files app. Have one host, have the other connect to it, two-way communication over WiFi. No AirDrop needed, they just have to both be on the same WiFi network (could be one’s hotspot).