Allow Customizing or Removing Prefixes for Series on Multi-Series Cards

[ixipixi]

Is your feature request related to a problem? Please describe.
When you add a series on top of a multi series card, every series in the legend is prefixed with the name of the card. This is often very long and makes the legend illegible.

Describe the solution you'd like
The option to set or remove the prefix entirely

Describe alternatives you've considered
Editing them one by one - this is fine if you have a few series but it gets cumbersome quickly if you have 20 + and/or multiple multi-series cards.