Thank you for your answer @janjongboom , I had a look and compiled successfully with Zephyr and the nRF Connect SDK. But have you ever heard about implementing edgeimpulse into the nRF5 SDK (so without Zephyr support) ?
@cyrilkoe Should be fine too, you just need to implement the few functions in https://github.com/edgeimpulse/inferencing-sdk-cpp/blob/master/porting/ei_classifier_porting.h so we know how to allocate memory / print things.
E.g. see the Zephyr one here: https://github.com/edgeimpulse/inferencing-sdk-cpp/blob/master/porting/zephyr/ei_classifier_porting.cpp - should be easy to change to nRF SDK w/o Zephyr.