Not sure if this helps, but the example that I came up with for the
quickstart https://orgmode.org/quickstart.html#macros has an example
(see below) of using multiple @@ export snippets in a single macro. If
you have consistent naming conventions for pdf vs svg you might be
able to write a variant #+macro: image that works like
{{{image(file-name-without-extension)}}}. Not sure this will get you
what you want though since I imagine that you want to modify how links
such as [[file:file-name.ext]] are exported. One alternative would be
to define a custom link type
https://orgmode.org/manual/Adding-Hyperlink-Types.html that would do
the type setting for you. If you want those definitions to live in the
org file you could use Eric's eval: (org-sbe startup) local variable
approach to ensure that the elisp definitions are always available.
Best,
Tom
The example from the quickstart:
#+MACRO: red @@html:<span class="red">$1</span>@@@@latex:\textcolor{red}{$1}@@
