Comparing and Visualizing Data Selections Across Two Tables

Hello everyone,

I need some help from the community.

I have 3 tables in my model, 1 MainTable, 1 AuxTable (a copy of the main one) and a bridge table to link the two.

I attached the link at the end of the post for the PBIX file.

Model:

What I need to do is compare the values selected in the slicer of my AuxTable (multiple selection) with the value selected from my MainTable (single selection).

I have the visual below that is already bringing the result of my slicer from the AuxTable. However, the average line (currently a constant line, I would like it to vary also according to the OXG field) so that I can compare the result of my aux selection with the single result of my main table slicer. I tried to use it in the secondary axis, but once I am using legend in my chart, I am not able to achieve this result and I need help from the community.

I also have a bar chart, which is being filtered by my AuxTable slicer, but I would like the selection of my MainTable slicer to also appear on the chart. Is there a way to do this?

I thank everyone in advance for your help.

Link to PBIX file: Here