Yes, that would be it: one work-item (acting as hub), x edition items connected to the work-item, each edition-item connected to its corresponding Wikisource page with a sitelink and, on Wikisource, an auto-generated nav bar that lists all sitelinks from all edition-items on the left (equivalent to the current interwiki link list). If there is more than one edition per language "author citation (P835)" or "author (P50)" value can be shown next to the language name. For connecting works with editions we already have "edition (P747)" and "edition of (P629)".
On Wikisource I don't think it is necessary to have always a "work page", this only happens when there is more than one edition for any given language. The most important part is to automate the creation of a work-item on Wikidata whenever is needed to link one edition to another (same or different languages) and, of course, show the generated nav bar on all edition pages .
Wikipedia(s) will be connected to the work-items as usual. "Template:Infobox book" needs some work to be able to show work- and edition-item data. I have started a proposal for this task as a possible Code-In, but maybe the second part needs arbitrary item access.
https://www.mediawiki.org/wiki/Google_Code-In#Lua_templates