All my metadata is added to notes using inline fields instead of YAML frontmatter.
I’d like to convert the inline fields for many hundreds, if not thousands, of files to YAML so that I can use the new properties feature from version 1.4.
Is there a way to do that?
I think your use case is so fresh that there are no plugins that offers a command to achieve that on single-note level. About multi-file processing: usually that is out of scope of Obsidian and other tools must be used.
In general you use some programming language or shell scripting to achieve multi-file processing. There are places like r/hireaprogrammer to reach people that offers programming. This could be useful to you if your work in Obsidian is very important and you don’t have time to see possible community solutions.
There are some threads already if you search with cue words YAML, metadata, convert, Python.
If your inline field properties are somewhere around the front matter (say under Heading 1 title), they could be captured by regular expressions and moved up into the frontmatter. That’s how I’d do it.
The rest you’d need to do manually.