I've noticed that from 1.92 array filters are managed with expression manager.
In particular I've noticed, tell me if I'm wrong, that expression manager use filter qCode to generate a !is_empty(qCode_sq)-like condition for each subquestion sq.
It would be very cool to give the possibility to use a relevance-like equation in the filter field in order to extend the possibility of array filter.

Here a scheme to explain better:

Q1: question
A1 A2 A3
SQ1
SQ2
SQ3

Q2: question2
A4 A5 A6
SQ1
SQ2
SQ3

Q2 filter_equation: (Q1==“A2” || Q1==“A3”)

this equation would generate (Q1_sq == “A2” || Q1_sq == “A3”) for each subquestion sq showing in the question Q2 only the subquestions that have answer A2 or A3 in question Q1

I've seen that this is similar to Idea #122, but I don't understand if the idea has been implemented as I've said in the first post.
I've to open a new feature request?

We haven't implemented sub-question-level relevance as you describe it yet. However, there is a viable work-around here.

The documentation explains how to do this.