I have to say I disagree with @Xavier_Jiang on the feasability of this idea. I actually think it should definitely be doable from a data transfer/energy standpoint.
Whilst the TPU benefits from a high speed interface, that is not really the limitation for expansion cards. Any expansion card should have a PCIe Gen 3 x4 available, which should be about 8 times the bandwidth required for that specific TPU card.
That is even enough to power an external GPU, which typically require monstrous amounts of bandwidth.
Power consumption is only up to 2 W, so I don’t suspect that to be a big problem, as normal expansion cards like HDMI and DisplayPort already seem to draw a constant 1W.
See: Linux battery life tuning
Whilst the Framework Laptop has a relatively powerful CPU/GPU combo, the big benefit here would be the performance/watt, which would be a lot more efficient than anything the Integrated GPU can do.
So for example a developer working on machine learning could benefit from these accelerator cards. Might be a great way to improve battery life.
I’m not sure whether the electronics will fit into an expansion card though…
In that case coming back to Xavier’s idea of simply moving the WiFi onto an expansion card and plugging the PCIe card into the slot for the WiFi module might just work.