Yes but you will need two MoCA adapters. You will have to wire like this...
ONT > ethernet > adapter > coax adapter > ethernet to router’s WAN port. "
Why do you need ethernet to the WAN port in that case? If the moca adapter connects to the coax, why can't the G1100 connect directly to a coax jack?
The G1100 can definitely connect to the ONT via the coax jack but only for speeds up to 100 mbps. The ONT uses WAN MoCA at 1000 MHz. The MoCA adapters use LAN MoCA at 1100-1175 MHz. If you want speeds higher than 100 mbps you need to run an ethernet directly from the ONT to your router’s WAN port. If you can’t run the ethernet then you need to use a pair of MoCA adapters.
ONT > ethernet > adapter > coax > adapter > ethernet to router.