MDT at Paragon Home Inspections, LLC wrote:
The NEC does not care

As a practical matter there is one exception to "it does not
matter" - if you have two or more duplets receptacles side by side it
makes sense to install them in *alternating orientations*, this makes
it more likely you will able to optimize your insertion of a
combinations of plugs and "wall-wart" transformers.

Everyone will make fun of your "sloppy" work, though 8^)

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That's heck of a good idea. Haven't got many'double' duplex outlets at
moment but it fits in with my idea!

When I wire a yet to be finished part of our basement am intending to
put in double duplex outlets, using square wall boxes; reason being
that adapters are messy, often cheaply made, tend to protrude from the
wall, may fall out etc. and do not accommodate sufficient plugs.

Also you do run into equipment cords that 'run off' in different
directions, sometimes at right angles (sideways) as it were. I keep any
old cut off equipment cords with odd configuration on the off chance
that they may be useful.

e.g. In kitchen we have a 'battery charger' for those small AA, D cell
batteries etc. whch has a moulded grounding plug, with cord that runs
off the plug oddly! Even though the charger is completely enclosed and
seemingly could use a two pin/polarized plug. Maybe the input-output/s
of the charger are electrically not isolated; although unit seems
heavy enough to contain an isolating transformer?

Also take a typical computer installation, (1) monitor, (2) the PC
itself (3) Modem or router (4) printer or scanner etc. That's four
sockets right there. The whole computer set up doesn't need a lot of
the power available on a 15 amp circuit/outlet. Then if you want to
plug in something else such as a radio or a soldering iron to do a
small repair you need an extension cord to the next outlet which is
hidden behind a heavy file cabinet or something!!!!

Similarly on work bench often have three items plugged in at same time
in order to work on something.

So double duplex outlets, installed in 'opposite' directions at about
waist level (just above desk-bench top height) it will be.

Thanks for the suggestion; oh, with a GFI outlet for downstream
protection in each circuit. Cos our panel is equipped with standard
Square D breakers, circa 1970s. Very happy that back then we installed
a 200 amp service and big enough panel; still got a few spare
positions!

Another idea; I may just install the duplex outlets 'sideways'?????????