Yes — in Darktable, reusable presets are usually shared as style files rather than XMP sidecars. XMP files are generally tied to a specific image and store file-specific edit data, so they are not the usual format for exchanging generic “looks.”

A community resource mentioned is dtstyle.net, which hosts Darktable .dtstyle files. You can import and manage these in the Styles panel in lighttable mode.

If you want Instagram-like filter effects, another option is Darktable’s LUT module, which lets you apply LUTs to create stylized color looks.

So, for learning and reusing edits:

• use .dtstyle files for shared Darktable styles
• use LUTs for many filter-style color effects
• don’t expect XMP sidecars to be the main shared preset format