I searched and did not find anything on this so I will ask.

I am about to replace the starter on my wife's 2006 Accord, 2.4L. To do this I have to remove the lower intake from the upper. There is a metal gasket here.

I wanted to confirm if that gasket is indeed reusable, or if I need to replace it.

 

I reused that metal gasket on my TSX. I essentially have the same engine as your wife's 06 accord.