Bitcoin Core 23.0 over Tor - strange incoming connection - local host IP?

Hi guys,

after some struggeling, I managed to run Bitcoin Core over Tor.I do not want to use the node from the Internet (for now) - it should just broadcast TXs and sync blocks over Tor.It looks like it's working since I have outgoing peers connected. But there is a strange incoming localhost connection within the peers list:

127.0.0.1:60805 (peer: 4) via 127.0.0.1:37150 

What is this? Can anyone help me understanding this?

Another question: Where is the difference between using

proxy=127.0.0.1:9050 

and

onion=127.0.0.1:9050 

(and even both together)?

Thanks in advance!