Issue with two Dell R620 servers connected directly with Cat5e cable get slow speeds

I'm trying to set up a new Hyper-V cluster to run my virtual environment on. Decided to try out 2019 and currently I have two HOST servers (Dell R620s) connected together using a cat5 cable directly (no switch). Each host has a total of 4 NICs (2x10Gb and 2x1Gb). The issue was really bad on one of the 10Gb NICs so I decided to do the tests on the 1Gb NICs on each server.

I have the other NICs connected to other things in my production environment but was getting mad about the slow speeds across the network so I wanted to do some testing...

HOST1 : 192.168.35.1 ...directly connected to... HOST2 : 192.168.35.2

On host1 I try to send over a large VM and this is the results...

Any idea what I might have configured wrong to make the network speed so bad? I have also disabled VMQ on all NICs just to test things out. Not sure if this is something with 2019 or maybe the NICs etc.

Thanks for any help!