Do any of the tank manufacturers offer an option to special order for a shadow overflow and they know exactly where to place the holes for it or do you have to send them a template?
Follow along with the video below to see how to install our site as a web app on your home screen.
Note: This feature may not be available in some browsers.
I don't think there should any problem with any of the manufacturer to do so. You can always ask them to make the holes for a shadow overflow when you get a custom quote. They may ask for a template which is available online and you may email them that for further help but I don't think all the big manufacturer actually need those template.
Key word here is "custom." Most tanks aren't purchased directly from the manufacturers, but from a retailer... again, unless it's a custom build. Side note: a respectable reef shop should be able to drill the tank for you if you don't want to do it yourself.
So, if you're doing a custom build no problem. An assembly line purchase will likely be a bit more work to pull off, but doable.
When OP asked that does any tank manufacture offer an option to "special order" for a shadow overflow I thought he is asking for custom order suggestion. As far manufacturer concern other than common aquariums like deep blue or marineland or some others nowadays major big aquarium makers can take direct orders from you and do home delivery. It doesn't need to be order through retailers anymore.
This is pretty much what I was looking for.I don't think there should any problem with any of the manufacturer to do so. You can always ask them to make the holes for a shadow overflow when you get a custom quote. They may ask for a template which is available online and you may email them that for further help but I don't think all the big manufacturer actually need those template.

