7i96E + 7i85S + AC Servo - encoder feedback

Thank you so much for answering my questions!
Everything starts to make sense now

One thing ist still not clear to me, you said

The correct setup number would be to enable as many modules as you need, the maximum numbers
of modules enabled would be 8 stepgens, 6 encoders, 2 sserials

There are 5 Stepgens on the 7i96 and 4 Diff Out aka Stepgens on the 7i85S, so that should mean there are 9 possible Stepgens, right?

I don't think 9 stepgens will fit in a 7I96+7I85S (unless some other feature was dropped)

Ok, so that means that it is a resource problem but if there were a bigger FPGA on the 7i96 the number would bee correct?

As I'm building a simple CNC mill with just XYZ (maybe a 4th axis later on) my config is:

3 stepgens
7I96 STEP 0 -> X Axis
7I96 STEP 1 -> Y Axis
7I96 STEP 2 -> Z Axis

5 encoders
7I96 ENC HAL ENC 0
7I96 ENC HAL ENC1 (alias of ENC 0) -> Spindle
7I85S ENC 0 HAL ENC 2 -> X Axis
7I85S ENC 1 HAL ENC 3 -> Y Axis
7I85S ENC 2 HAL ENC 4 -> Z Axis

And of course the SmartSerial if I want to use them for more IOs.

The left Stepgen and the Differential Outputs on the 7I85S can be used as normal outputs!?

Is that correct?