You may keep the core photographic metadata when converting ARW to DNG, but you should expect that some Sony-specific maker-note data can be lost, changed, or remapped depending on the converter.

From the answers here: standard EXIF such as aperture, shutter speed, focal length, and flash status is generally preserved. Some proprietary fields—lens ID was specifically mentioned—may be lost in some conversions, while other converters may carry that data over or move it into more standard XMP-style fields.

So the practical answer is: DNG is not guaranteed to preserve every proprietary Sony tag exactly as-is. Converter behavior matters.

If that metadata matters to you, the safest approach is to keep the original ARW files, even if you also generate DNGs for workflow or compatibility reasons. DNG can be useful as a documented, widely supported container, but it is still a conversion from the camera’s native raw format, and not every camera-specific detail is guaranteed to survive unchanged.