AddHandler Hide Labels.

Public Class Form1
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Dim ctl As Control
        For Each ctl In Me.Controls
            If TypeOf ctl Is Label Then
                AddHandler ctl.MouseEnter, AddressOf Label_MouseEnter
            End If
        Next ctl
    End Sub

    Private Sub Label_MouseEnter(sender As Object, e As EventArgs)
        DirectCast(sender, System.Windows.Forms.Label).Visible = False
    End Sub
End Class