We have found one software suitable in our database for this conversion.
bww to mxl conversion represents export of music scores from between Bagpipe Music Write music notations (.bww) and a compressed version of the MusicXML notation files (.mxl). Considering that MuseScore supports import of BWW format just fine, it's the obvious as well as most convenient choice for this export.
Updated: October 9, 2023
BWW
Files with bww extension are music notations made using the Bagpipe Music Writer, a dedicated software for writing bagpipe scores.
MXL
An mxl file extension is related to the Compressed MusicXML notation format used to store music notation. An mxl format is used by ENCORE!, Capella, MuseScore and others.