Making Diplomacy Checks Remotely

[unseenmage]

Was fiddling with some Greater Humanoid Essence ideas and it occurred to me to wonder if Diplomacy checks can be made from afar?
If so how far? And via what means?
Illusory projection? A hand-penned letter? Magic Mouth spell?

General Diplomancer discussion encouraged as well.
Especially where Diplomancy and Construct/Undead Control intersect. :smalltongue:

[Curmudgeon]

Diplomacy is delivered via speech. If the target can't succeed at a Listen check to hear your speech, you can't use Diplomacy. If you've got a way to project your voice to the target so they can make their Listen check, you can (try to) use Diplomacy. Seems pretty simple to me. You can't use a Magic Mouth for Diplomacy.
Action: Changing others’ attitudes with Diplomacy generally takes at least 1 full minute (10 consecutive full-round actions). In some situations, this time requirement may greatly increase.