Which camera is good for streaming on twitch? 1080p! No webcam and a maximum of 500 euro!
Maybe a GoPro Hero 7?
You go to http://www.test.de and then look for the products on http://www.idealo.de/....idealo.de
EOS M50 or Sony A6000. In order to stream permanently you would need a power adapter.
Practically every camera that can output a live image via HDMI can do this.
For example, a Sony alpha 5000 would be very cheap, it is also nice and small, has an APSC sensor and you have enough budget to buy a decent lens (for example the SEL50F18).
You also need a battery dummy and a Camlink (HDMI Capture Card) for this to work properly.