I have a table with a lookup from another table in a grid view in which the result is Brown. When I go to the calendar view to select the field for the color, it’s not in the list of options.
As @ScottWorld said, there’s no default way to do this.
However, there is a workaround that, while a little clunky, definitely will accomplish what you’re looking for. It requires setting up an automation that watches for when a record is linked, and then copies the linked color to a single-select field in the same table as the desired calendar view.
Here’s a quick walkthrough I recorded on setting this up for your base.