I thought the 4G boosters just do that? So amplify the signal inside the house, without physically being connected to any other device*? It is quite an installation; antenna on the roof, cable to amplifier, etc. I guess the small in-house solutions are much weaker.
*unless you can connect the router
And are there with these boosters always wired solutions available which provide the connection from booster to the antenna connector of the (TP Link) 4G router? Because these routers do not have a port for that. (Only Ethernet, power and SIM.) I guess the booster provides the same TS9 coax cable as the external antenna you can buy on Tokopedia etc.? So then you would replace an antenna with the cable coming from the booster.
I have used antenna boosters / amplifiers on the DVB-T signal for a TV. With an ultra high dBi (17) to be sure. But the results were bad, bit of a wasted expense. I hope that one for 4G works better.
I switched from XL to Telkomsel mainly because the signal in my house was terrible. WiFi is separated from all this of course; with some antenna replacements (longer model) addition of aluminium foil (really!) and realignment of antennas on the router and addition of amplifiers (one via Ethernet, the others wireless) I have been able to cover the whole house.