I would have my alternative titles (per language) in custom metadata fields (text) of their own. One per language.
In my compile format, I would uncheck the title if I only want the new title.
Put my placeholder pointing to a specific title-language as the title’s prefix.
Format it in the formatting panel.
[Same as above, with the binder title included, and the placeholder as a suffix, if it is an extra.]
Once I’d have a section layout that matches my needs, I’d duplicate it, and adapt the title prefix’s placeholder to target the other languages’ custom metadata fields.
Once this is set, I’d compile using the appropriate section layout. (One or a set per language.)
I’d rather create complete compile formats (duplicates of the first one), one per language, if using section layouts inside a single compile format grows too complex.
. . . . . . .
That’d be one way to do it. I’m sure there are a couple more.
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After reading your post again, I realize I misunderstood the question somewhat.
You want this at the top of your pages?
Then you could create a binder document that has only a title and no content.
Compile it through a section layout that excludes everything.
But make it your PageGroup parent in the binder (?) and use <$pageGroupParentTitle> in the page setup. (?)
Personally, at this point I would just post-edit it in, using LibreOffice or whatever.
Another thing you could do is name the binder element what you want the running header to be, and title your document as it should appear, formatted using a style, directly in the document. This way you don’t need extra documents.
Uncheck the title from your section layout, and use your <$pageGroupTitle> in the page setup.
I still would prefer to post-edit it in, using a third party app.