I want to use the updateall feature on a regular basis but I only want to copy the files different in size. Can I use this command with this "adjustment"?
Copy UPDATEALL always considers both size and date. I don't think there is a way to make it consider just the date.
Copy UPDATEEXISTING and the Synchronize tool can both be made to consider just the date.
I guess you could make a button which does an UPDATEEXISTING followed by a command which copies over all the new files. I haven't tested this but I think it should work: