PCIe x16 GPU card into a PCIe x8 slot?

A PCIe x8 slot has a physical length of approximately 56mm and has a single notch on the connector, similar to PCIe x1 and x4 slots PCIe x8 devices are

You could have an efficient GPU in the laptop expansion board, plus connector to push out the 8x PCIe Then you could have the latest gen

pcie m2 slot if the slot is open like that, you should be good to go if it's not open, you could a) use another riser to adapt the x8 to x16, or b)

pcie nvme slot If it's an 'open-ended' PCIe slot with say 76 connectors in the 'major' half but will still