Dunno. I’ve got 3 phase, 400V, 100A service which results in 68kW useable. However, because one of sub junction boxes which, unfortunately the wall boxes are connected to is wired internally with 10mm², I’ve enabled peer to peer load management across my wallboxes for now so they never pull more than 28A per phase. Most cars here support three phase charging so that’s still fine even for two cars. I’ll get to rewiring that, for now it works.
The go-e wallboxes I have support a central controller which in turn can measure current on all three phases into the home, e.g. to use a solar system to its maximum, but also to limit absolute load on the house connection. They just use three hall sensors for power measurement as far as I know, so installation is relatively unintrusive.
I went without that and solved the whole solar optimization using EVCC and regarding absolute load I’m just yoloing it, but then again, I do have a neat safety margin.