Currently the EinsumsPy module is using pybind11::embed, which links the python library, rather than pybind11::module, as it should. All the usual symbol errors if you try to downgrade to module. From testing, this doesn't come about from the einsumspy code but from the need to link it to the Einsums::Einsums target. You can take a generic toy pb11 module and upon applying the first line below, it also needs the second. This should be remedied evenually.

target_link_libraries(pyeinsums PRIVATE Einsums::Einsums)
target_link_libraries(pyeinsums PRIVATE pybind11::embed)