Yes, the upstream device setting is defined for the HA Energy dashboard, but is global in the sin that it is used as well when additional Sankey Cards are placed on other dashboards.
As far as I know however, you can not access these upstream settings outside of the Energy dashboard cards.
The advantage of using the Sankey card on another dashboard is that you have extra configuration options: you can set the visibility of the floors and areas (true or false).
This is an example of a Sankey card with both set to true:
type: energy-sankey
title: Energy flow
layout: horizontal
group_by_area: true
group_by_floor: true
Personally I am not using the upstream devices setting because this still removes the floors and areas from the Sankey chart on the native Energy dashboard, but with the Sankey card on another dashboard and with the floors and areas set to true all levels are visible.
As a test I added one upstream device setting, and this is the result:
This however clearly isn´t a very useful graph, with the entity names unreadable.
Personally I am not so much into fancy dashboard lay-outs, and I have no idea whether it is possible to get a larger graph on the dashboard. Can someone else with more knowledge on dashboard lay-outs comment on this please?