I think it needs an integrated connection for a MICROPHONE and a great camera. It's only supposed to be Twitch and therefore I wouldn't care about any unrelated functions. Cool would be a cheap price!
If you want a great camera you just have to choose a flagship from any brand, see if it has a jack connection and you can then buy it.
Well Unfortunately, that doesn't make you any smarter. So you still don't know which camera is good and where a micro connector is integrated. There's nothing like that anywhere!
The iphone is best for videos, you don't need to buy a microphone, but you can connect a microphone to any
The iphone 11 / pro or the 12 series are very suitable for this if you have the money
Otherwise, if you want to spend less, the Google Pixel 4a would be a good option (but only if you use the rear camera)
If you have eyes you can see in pictures whether there's an aux connection and I hardly think that Apple, for example, has worsened its camera with the new generation.