The project's FAQ are kinda enlightening: https://github.com/Euro-Office#faq

Your question is somewhat answered there: "What is Euro-Office?", "How does Euro-Office compare to IONOS Workspace, office.eu, the Proton productivity suite, Nextcloud Hub or XWiki?"

However especially "Why was a new office suite needed" is telling.

True EU sovereignty spells: the only requirement is, it must work "greatly" with MS. Oh well, in the past libreoffice and the likes mostly chose open formats as their reason.

If EU sovereignty means simply being a rip off, you get into trouble my friends. This is Chinas business and doesn't spell innovation nor does it mean optimism for the future.