8 – How to list entities and sort them by delta?

I have a “stations” and “railways” node types and a custom “notification” entity type.
In “railways” node type I have an entity reference field (“field_stations”) where I can select “stations” nodes which is good.
In “notification” entity type I have an entity reference field where I can select related stations. (entity reference to “stations” nodes)
I would like to create a view to list “stations” nodes with grouping and sorting. I would like to group them by “railways” and sort them by delta (“field_stations”).

I tried it but I could not get the right order and get a lot of duplications. I have tried views_order_by_delta module as well with no luck.

Do you have any recommendations?