No, it is not possible to enable "Auto-Rotate with Edge" with instructions in the label text.
What you can do is the following:
Create a dedicated column (let us say "rotate") in your spreadsheet that is part of the "Edge List" data range.
After importing your spreadsheet, use "Tools" -> "Select Elements" to select all edges for which "rotate" is set to whatever value you have chosen to mean "text should be rotated".
Click "Auto-Rotate with Edge" in the properties view in yEd's lower right corner to enable the feature for the selected edge labels.