If you have mnay controls on your Form and do not want to add the same code to all their MouseMove events, simply use the following instead.

Add it to a Form with a Timer and a CommandButton.
Code:
Private Declare Function WindowFromPoint Lib "user32" (ByVal xPoint As Long, ByVal yPoint As Long) As Long
Private Declare Function GetCursorPos Lib "user32" (lpPoint As POINTAPI) As Long
Private Type POINTAPI
    x As Long
    y As Long
End Type


Private Sub Form_Load()
    Timer1.Interval = 1
End Sub

Private Sub Timer1_Timer()

    Dim PT As POINTAPI
    Dim WND As Long
    
    'Get the Cursor postion and the hWnd it's on
    GetCursorPos PT
    WND = WindowFromPoint(PT.x, PT.y)
    
    'Check if the hWnd the mouse is over is Command1
    If WND = Command1.hWnd Then Command1.Caption = "Mouse is on Command1" Else Command1.Caption = "Mouse is not on Command1"
    
End Sub