One scenario one sees often is the idea of shooting macro at a greater distance with the hopes of avoiding a narrow dof, and instead cropping later. I'm pretty sure you covered that situation and that turns out to be a 'no free lunch' kind of thing, since the cropping would take back the dof that shooting from farther away initially had.
Nobody seems to have answered this detail.
In the Mirrorless era, some might suggest this is an obsolete issue
This is because at f5.6 and wider with good eyesight you normally see the exact depth of field in the viewfinder.
In addition at smaller than f5.6 using a custom function to show real time depth of field at smaller than f5.6 apertures there is a bright image clearly showing the depth of field that you are getting.
When you can distinctly see the zone of sharpness in the viewfinder (as you can with ML) - depth of field formulae debates are much less needed.
For most practical purposes
for macro work there is no practical difference with a different focal length lens though there is a small mathematical difference.
As an example if you focus at 1/40th of HD dof is 1/41
of focus distance in front of the point of focus, and one 1/39 behind.
In practical photographic terms dof is equal both sides of the point of focus -
for macro image sizes.
If you double the focal length you are likely to be at 1/80 HD - with 1/81
of the doubled focus distance acceptably sharp in front and 1/79 sharp behind.
The result is no practical difference in depth of field
There is a Nikon macro (and a few other lenses)
"however"
At infinity focus these lenses use an f8 app size when f8 is selected.
By 1:1 they physically open up the f8 aperture to around f5.6 - with 1 stop less dof.
In addition they focus breathe by about 1 stop loosing about another stop depth of field.
The overall effect is that at 1:1 an infinity exposure time is used rather than minus 2 stops that close up formulae suggests is required at 1:1 focus.
Some old symmetrical lens designs that do not do either have about 2 stops different dof at 1:1 than Nikon AF macro lenses, offset by a 2 stops increase in exposure time.
Another important detail for relative novices is that depth of field formula assumes as a starting point t
hat the image whether first cropped or not is enlarged enough to produce a 10 x 8 inch print.
To achieve this requires more detail in the DX image - mathematically needing a smaller circle of confusion for depth of field calculations.
Although it may initially sound counter intuitive a smaller circle of confusion results in an increase in depth of field.
As a result you get about one stop more depth of field when maintaining the focuse distance, angle of view and aperture with DX compared to FX.
Repeating what I said near the start, one of the advantages of ML is that with good eyesight you can easily see the depth of field you are getting in the viewfinder - making a need for dof calculations more redundant than they used to be.
One of the advantages of some current PP software is you can focus stack several images to double of treble dof - perhaps lets not go down this rabbit hole.
