I think you're going to run into problems with that approach because of the frequency range consumer wireless operates at (2.4 GHz and 5 GHz). The typical RV coaxial wiring often seems to use 1 GHz F connectors and has hidden splitters in the walls, neither of which will work. The satellite connection *might* be a direct line with high frequency connectors, but that is not easily tested in advance without buying an expensive meter or the wireless equipment you would use. Something like this would be where I'd start my hardware research: https://www.ubnt.com/unifi/unifi-ap-outdoor/. You should be able to get adapters to convert what looks like SMA connectors to the trailer's F connector, but I'm unsure of how the performance will be.
I actually just installed a setup like this on our trailer this weekend. I installed:
(1) External 3 GHz F-connector port
(1) External RJ-45 port
(1) Dual rocker switch
(1) PoE injector (attached to one of the switches)
(1) weBoost 4G-X RV with 12V hardwiring (attached to the other switch)
(2) Dual 2.1 amp USB ports
The coax-based portions are for attaching a Yagi antenna for the weBoost where the ethernet-based portions are for a Ubiquiti NanoStation M2 to extend the WiFi range significantly. The extra USB ports are to power the local router and AT&T ZTE Mobley.
Both the NanoStation and Yagi antenna are attached to a telescopic mast that will be installed where needed via suction cups on the side of the trailer. I did not want to permanently install this because I wanted the option to both reposition it if the overhead was obstructed by trees and to allow for it to be much higher than the trailer roof.
I have photos that I can append from a computer if wanted (on an iPad at the moment).