diferentes maneiras de enviar caracteres Unicode no AutoHotkey:
vText := Chr(0x3C9)
SendInput %vText%
SendInput {U+03C9}
WinGet, hWnd, ID, A
ControlGetFocus, vCtlClassNN, ahk_id %hWnd%
PostMessage, 0x102, 0x3C9, 1, %vCtlClassNN%, ahk_id %hWnd% ;WM_CHAR