To convert presets into files—a common step for using Lightroom Desktop presets on the free mobile app—you don't actually use a standalone "converter" program. Instead, you use a photo as a "carrier" for the data. Since XMP files are text-based instructions rather than images, the process involves applying those instructions to an image and saving that image as a DNG. Free Methods to Convert XMP to DNG
: This is the industry-standard free utility for converting camera-specific RAW files into the universal DNG format. If your RAW files have sidecar XMP files in the same folder, the converter typically embeds that metadata into the resulting DNG. Lightroom Classic / CC
Free XMP to DNG Converter: A Game-Changer for Photographers
The Honest Reality Check: Adobe DNG Converter is designed to convert Raw Image Files to DNG images. It is not designed to convert a standalone text file (XMP) into an image file (DNG) without a source image attached.