Private Sub Button1_MouseHover(sender As Object, e As EventArgs) Handles Button1.MouseHover
        Button1.Text = "Mouse"
    End Sub

Private Sub Button1_MouseLeave(sender As Object, e As EventArgs) Handles Button1.MouseLeave
        Button1.Text = "button"
    End Sub

Mình thử ở VB cái MouseHover và MouseLeave làm đc b ạ.