Remote sensor outside of HA reach: transfer data via HA phone app?

I have an electricity meter in the basement (3 floors down from my flat) and I’m looking for a way to read the data from it and send it to my HA instance (running on Raspberry if it’s important). Obviously, there is no way to put a cable between my flat and the counter and neither any signal can reach thru multiple walls and floors.

The idea I had in mind is to have the reading device attached to the counter with some kind of power bank which would record and save the data locally (let’s say on the sensor) and when I’m around with the phone and installed HA app, it could dump the data to my phone and then to the actual HA instance.
Of course it would be great to have the real-time data, but given the situation I’d be fine with quite infrequent “syncronizations”, let’s say 1-3 times per week (when I actually go to the basement).

Does it sound like something which is possible to implement without too many issues? What would you recommend, how to set it up? Any other ideas (just though that I might try to use some kind of powerlan to transfer the data via electric lines, but I have never worked with it, so not sure how does it actually work…)

How about an Ethernet over powerline adaptor pair?

Might be, haven’t tried this, but feels like the cost of trying would be still noticeably more than hacking something on software side…