Welcome to the Q&A Forum

1. Search Console tells you, that they use a canonical for the homepage, that doesn't mean John Mueller is talking about that in this webmaster hangout (https://www.youtube.com/watch?v=WAagTHeF9N0) 2. I can just guess, think it could be a structure thing, and maybe it is to fresh - 6 month old site with several regions set-up in same language. So a lot of duplicates, canonicals aso Google has to deal with. And of course, Homepage is strong, your landingpage may not be strong enaugh.   And whatever happens on Googles Page 5 is more or less useless data. If it still happens when you are on page 2, guess than there is a real problem.  At the moment, without knowing anything, asuming hreflangs, canonicals are right, think it is a structure, time, pagerank combined thing. 3. You can use canonicals and it depends, if you need them, you need them - no matter if hreflang in use or not.  You have to send the same signals, not confusing once. I think here is helpful stuf about hreflang and canonicals working together (https://www.searchviu.com/en/hreflang-canonical/) 4. It depends on depth, difficulty, and a lot more factors. I cant say anything here without topic or domain / page 5. You use hreflang, so you tell google what to rank where. Sending confusing signals (hreflang to a page wich has a canonical to anywhere wich has an hreflang-back  to that page. Nice confusing chain... ) google will start to ignore your canonicals in this case Hope that helps a bit

You will want to set up multilingual hreflang tags across all pages. This will essentially tell crawlers "each of these URLs are actually the same 'page'. You should show the correct version based on the location of the visitor" which prevents them from treating it as duplicate content.