Hide Chart from legend but show in chart

[zimbo86]

Is your feature request related to a problem? Please describe.
I want to add horizontal lines to mark a specific threshold.
For example I want to highlight "32°C" in this chart:

One way to do this is a template sensor in HA, which has the line value as state.
Another way is to use any dummy sensor and add
transform: return 32

Describe the solution you'd like
In both cases i would like to have the option, to hide this entity from the legend (here: Schwelle)

A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]

[Aephir]

I would love this, but for a different reason.

I have a graph with "raw" and "total" electricity prices. The prices for "today" and "tomorrow" are different series (for reasons related to when during the day they become available, and whether to use "forecast" or "real" data for "tomorrow").

However, I don't want both "Total Today" and "Total Tomorrow" listed in legends, I want to hide one, and just display the other as "Total" (same for "raw").