Logseq has the ability to convert org to markdown and vice verse.
Expose a function for plugins to convert text between these two formats.
Many online note-taking apps provide a markdown export, but it is very hard to sync them to org files. Or plugins such as mark-map could work better for org files.
For syncing, a short term solution may be the ability to create notes in not preferred format. For other uses, a conversion function is still necessary.