Back in the day in our house in Singapore, that was built like a pre-war bunker with near-impossible wifi propagation, I solved the issue with Power-line communication (PLC), or rather Broadband over power line (BPL), i.e. using the house's own electricity cabling to propagate the internet signal from plug to plug. One plug for the router, and as many plugs as needed for access points. It worked like a charm, and it provided speed identical to cabled ethernet (which it is, in essence). Some plugs have a wifi repeater built-in, to support mobile devices.
In our condo in Bangkok, which presents the same challenge, I installed a Mesh solution, which works fine, but eventually I asked the management to install a second router directly accessing my home office. It required additional outside cabling and gutting of ceilings, but it works like a charm. We now have 2 different wifi networks, but that's not an issue for me.
I think that Broadband over power line (BPL) is a hidden gem, that solves the problem without requiring any hacking.