Changing my network Possibly

[Donut417]

I had an option to switch bed rooms to a bigger room. The issue was I have an HD Homerun and the antenna needs to be in my current bedroom due to reception. So I was thinking moca could work here, so I drew out some options and wanted some thoughts. For some background info, the room is slightly down the hall. I have attic access in the new room, I was going to put a moca filter and two way splitter on the line directly in the attic. That line is currently used for HSI from Xfinity (150/10). I was going to just buy 2 actiontech bonded adapters. Firstly as these have two coax connection, do I need a terminator for the adapter where im not using the second coax port? From my understanding interference can get in to open coax ports and cause issues with the cable system. Secondly, I know some people recommend a moca filter directly on the modem, would anyone suggest that? Or is that for Docsis 3.1 modems, due to the fact they can use the higher frequencies? Third, can anyone recommend good splitter? Any other recommendations are welcome. What im trying to figure out is how much this could cost me, if too much then I will just forget it.