Can I batch change documents' font and size?

I have 40 odt files, is there a way to format their text to one font and one size, without manually opening each doc?

It’s 40 recipes I’ve tried and written cooking notes about, and I haven’t been consistent about conventions…like - deciding that each recipe title is size 15, the source of the recipe be it a book or a site is in size 11 and grey, right under the title…bla bla…

So I’d like to make the documents equal as possible and go from there.