That's ok. HR departments were going to trash the formatting even if it looked good in MS Word.

They manage to trash the formattimg for plain text resumes too.

It's not just between LibreOffice and Word. Up until at least Office 2016, .docx formatting would regularly break for me between Word versions or between Office for Windows/Mac. Admittedly, Microsoft has got better with this as of late, but the .odt format is much more solid.

Formatting for docx files isn't the same between modern desktop Word, and the online version either, I've had trouble with tables for example.

I stick to PDF for that sort of thing. No need for them to edit your resume, right?

I've had recruiters ask for editable resumes because they don't want to reveal your name until you've gone far along enough in the hiring pipeline.

I'd just send them a blank named PDF document copy if that was their only justification.

In all likliehood, they're going to copy and paste your resume into their tracker, and it's going to look like garbage regardless.