It is not possible to use SATA to connect two computers together, mainly because it is a host/device topology. This means the host sends a special "host-to-device" command, and the device sends different "device-to-host" commands back.
It would be possible to connect two computers using SATA with your special SATA translator device in the middle just like USB cables .You can't connect two computers together with a bare USB cable, because they are both hosts with no devices to talk to.