The short answer is “yes.” The slightly longer answer is that LO will warn you when you “Save As…” and select docx, xlsx, etc. that some LO features may not be compatible with Word, Excel, etc. and therefore may be lost if you save in that format.
My suggestion: save often, and check your output for any changes made between saves. Under most circumstances, I suspect you will be just fine.
One quick note concerning macros. VBA macros may not run “as is” in LO, but I’m not aware that they will be disturbed either – so they should be there in the docx, xlsx, etc. file after you save (but I repeat my advice concerning saving often and checking changes between saves).
Hope this helps.
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