How to connect iMac 5k 2017 to Eizo screen?

You plug this USB-C to DVI-I cable into the one of the Thunderbolt 3 ports on the iMac, and the other in the Eizo DVI-I port. Then you consolidate the displays after the connection and power-up of the Eizo via the System Preferences : Displays : Arrangement tab. It would look like this (I am using an Acer 27 inch display with my Late-2013 iMac):

and this allows me to drag the mouse off the right side of the iMac onto the external display. You may also need to recalibrate your attached Eizo too.

I double-checked the Eizo model's particular port specifications to ensure it was really DVI-I and not DVI-D, before recommending the link to the cable in my previous post. Your diagram reinforces where to plug the DVI-I end of the cable into the Eizo monitor.

Glad to hear that you found a USB-C to DVI adapter that works.

You're welcome.

The Monitor connection on the left is digital DVI-I and the connection on the right is analog VGA/D-Sub.

You will need to connect to the monitors left digital DVI-I input.

To do that, you can use the cable the VikingOSX has suggested above.

Or you can use the following USB-C to DVI adapter and a DVI cable.

https://www.startech.com/AV/display-and-video-adapters/usb-c-video-adapters/usb-c-dvi-adapter~CDP2DVI