XMP versus lrtemplate: which format do you need
Which preset format you need depends on your version of Lightroom. Lightroom Classic 7.3 and newer, as well as Lightroom CC (the cloud version) and Adobe Camera Raw 10.3+, work with XMP files. Older versions of Lightroom use the lrtemplate format.
The practical difference: XMP files are simple text files in an open format, they load faster and are compatible with more software. lrtemplate files are a proprietary Adobe format with declining support.
At fotografie-presets.nl we deliver XMP files as standard. If you do work with an older version, you can manually convert XMP files via Lightroom: import the XMP file, right-click it, choose "Export" and save as lrtemplate.
Our advice: where you can choose, work with XMP. It is the standard for the future and works across all Adobe products that support Lightroom editing.