Hi @Raphael_Henri  Have you tried building a simple Keras Sequential 1 model and running tf.keras.Model.summary to check the shapes? E.g. the Create the convolutional base step section in Convolutional Neural Network (CNN)  |  TensorFlow Core but with a softmax 1 layer for probabilities.
Also, check out this example:

  
      

      keras.io
  

  
    

Keras documentation: Timeseries classification from scratch 1