Hi there.

It's called Google knowledge graph. It's being created automatically, but you can "help" Google to understand what you want to display.

Refer to this google page for more detailed explanations and how-tos: https://developers.google.com/structured-data/customize/overview

Hi.

Interesting, I didn't see that article. Well, then, I guess, it's matter of preference.

I'd still go with different sitemaps. cause managing them individually allows script and code based automation.

Hi.

Sitemaps are done per domain, that's for sure. And use of hreflang is just saying that "Here is a link to a different language version of the website you're on right now". So, it doesn't cover both websites.

Example:
You went to Paris and bought a map of Paris with labels all in french. As you're looking at that map, you have no clue what those labels say, since you can't speak/write/read French. Then you notice that at the bottom of this map there is a sentence "To buy a map of Paris in english, go to such-and-such store".
Now, does that sentence (reference) help you anyhow to translate what's on a map you're holding in your hands? No.

The same thing with sitemaps. Reference to a different language version of the website doesn't pass the content of that website. Especially, since you have all URLs in different languages.

Long answer short - you'll need to sitemaps.

Hope this makes sense and helps.

Hello, my friend.

I say go with with first solution - target both keywords, because they are very much related and you can very much naturally bond them. It's not the best practice if you're trying to target two non-related keywords on the same page, when they shouldn't even be on the same page. In your case it's not an issue whatsoever.

Cheers.

Hi there.

Actually, your plan is very good. That's actually what Matt Cutts recommends in this video https://www.youtube.com/watch?v=EcSsMbFSGyc&t=160. I think we can trust his word

Hello, my friend.

It means bolded text. Or any elements which are inside or tags.