Probably a cousin to 🇧🇷 Lucro. Sometimes the best way to find the etymology of a Portuguese word is to look up a related one in etymonline, so words like this are very helpful.

Cool, thx

When can we expect it?

By that definition at least

I thought viable offspring meant "children who can have children of their own". But yeah, I don't think "being of the same species" is a transitive relation

Oh yeah, that makes sense. It's not even all of Brazil (and perhaps less common than I thought at first).

There are a few examples on Forvo where it's more evident (look at the "Espero estudar direito"):
forvo.com/search/estud...

The i might be half-way between a fully pronounced E and just a S? Not sure

I'd say it's more like "Elis istudam" or "Eliz istudam". The E-->I switch is quite commum in pronounced portuguese