How do I remove the stand to transport my iMac 2019?

The stand on 2012-2020 iMacs is NOT removable. It is part of the chassis. The ONLY method of removing it is to saw it off which is NOT recommended. If you need to transport your iMac use the original box or go to a shipping store and ask them to prepare a box for shipping.

You can also look on Amazon for other shipping solutions for iMacs.

The link that you posted is deceiving. As mentioned, the stand only comes off of some very early 2006 -2011 iMac models.

If you do not have the original box and packing, then an iLugger is a good option.

see > https://www.ilugger.com

If by "transporting" your iMac, I'm assuming putting it into your car to take it somewhere. I normally use the box that came with it, but if that is not an option, I just place a nice, thick town on the seat/trunk and lay my iMac flag - LCD facing down - on the towel. Never had an issue.

There is zero need to "saw it off".

[Edited by Moderator]

That is incorrect information, the stand is not removable in any way on 2012-2020 iMacs.