After further testing guided by Hans’ suggestion, I now have

\setupexternalfigures[location=default]
\setuplayer[preset=rightbottom, method=overlay]{}
\setuppagenumbering[color=darkmagenta]
\starttext
\getfiguredimensions[HannahBW.pdf]

\dorecurse{\noffigurepages}{
\startTEXpage[pagestate=start]
\layeredtext[]
[boffset=3pc, roffset=3pc]
{\darkmagenta\subpagenumber}
{\externalfigure[HannahBW.pdf][page=#1]}
\stopTEXpage
}
\stoptext

which works, though it would arguably be better if there is a way to prevent the subpage number on the first page of every included file.

Alan

On Fri, Sep 25, 2020 at 6:12 AM Hans Hagen <j.hagen@xs4all.nl> wrote:
On 9/25/2020 5:53 AM, Aditya Mahajan wrote:
> On Fri, 25 Sep 2020, Wolfgang Schuster wrote:
>
>> Aditya Mahajan schrieb am 24.09.2020 um 23:48:
>>> On Thu, 24 Sep 2020, Alan Bowen wrote:
>>>> Any suggestions or pointers will be most welcome.
>>>
>>> See if this gives you any ideas ....
>>>
>>> https://adityam.github.io/context-blog/post/include-multi-page-pdf/
>>
>> When both document have the same size you can replace TeXpage with a "page"
>> layout.
>>
>> \startlayout[page]
>> \dorecurse{\noffigurepages}{\externalfigure[...][page=\recurselevel]}
>> \stoplayout
>
> Thanks for the comment (also I didn't know about \startlayout .. \stoplayout). Unfortunately, in my use case, the paper sizes may not be the same.. I am typically attaching published journal articles and some are published on letter paper and some on A4.

\setupexternalfigures[location=default]

\starttext

\dorecurse {5} {Before #1\page}

\getfiguredimensions[oeps.pdf]

\startsetups SomeNumber
     \vbox to \overlayheight \bgroup
         \vss
         \hbox to \overlaywidth \bgroup
             \hss
                 \bfd \red You can figure it out: \pagenumber
             \hss
         \egroup
         \vss
     \egroup
\stopsetups

\defineoverlay[SomeNumber][\setups{SomeNumber}]

\dorecurse {\noffigurepages} {
     \startTEXpage[pagestate=start]
         \externalfigure[oeps.pdf][page=#1,background=SomeNumber]%
     \stopTEXpage
}

\dorecurse {5} {After #1\page}

\stoptext

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                                           Hans Hagen | PRAGMA ADE
               Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
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