Hola, no tengo formas de probar pero haver si funciona con algunas de estas
Private Declare Function SendMessageLong Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
Private Const WM_IME_CHAR As Long = &H286
Private Function SetWindowTextEx(hwnd As Long, Text As String)
Dim i As Integer
Dim Key As Integer
For i = 1 To Len(Text)
Key = Asc(Mid(Text, i, 1))
Call SendMessageLong(hwnd, WM_IME_CHAR, Key, 0)
Next
End Function
Private Declare Function PostMessage Lib "user32.dll" Alias "PostMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
Private Const WM_IME_KEYDOWN As Long = &H290
Private Function SetWindowTextEx(hwnd As Long, Text As String)
Dim i As Integer
Dim Key As Integer
For i = 1 To Len(Text)
Key = Asc(Mid(Text, i, 1))
Call PostMessage(hwnd, WM_IME_KEYDOWN, Key, 0&)
Next
End Function
PD: tengo mi duda si estas obteniendo bien el hwnd, creo que esto esta mal o de mas, hParent = GetParent(hWindow )