Learn Portuguese (Portugal): Eles são casados e estão em Lisboa.

In Portuguese, marital status is generally treated as a defining, long-term characteristic of who you are, rather than a temporary condition. That's why we use ser (são casados) instead of estar.

Why do we switch to estão (from estar) for being in Lisbon?

The verb estar is always used for physical location. Whether they are just visiting for the weekend or have lived there their whole lives, you must use estar to say where someone or something is located.

Why does casados end with an -s?

In Portuguese, adjectives must match the noun or pronoun they describe in both gender (masculine/feminine) and number (singular/plural). Since Eles (they) is plural, the word casado gets an -s added to the end to become casados.

Does Eles mean this sentence is only about two or more men?

Not necessarily! While Eles does mean "they" for a group of men, it is also the default pronoun for any mixed-gender group. As long as there is at least one male in the group, you use Eles.