If I crack a "Legacy" pack, is it possible to get Boba Fett, Han Solo, Luke Skywalker or other "Starter" card as the rare? If so, are those considered "Rares" or "Legendaries"?

TIA

You cannot. Starter cards from Legacies are exclusive to the starter decks.

To expand, the starter sets do usually come with a few cards that ARE found in legacies packs, but those are always the same and they're mostly commons. As RJM said though, there are a bunch of cards that are exclusive to starter sets that you will only find there.

The original Starter Sets in Awakenings had some fixed cards, and then some rares that were also found in packs. This was ABSOLUTELY HORRIBLE, as it meant that any pack with a starter rare in it was as useful as burning the money you use to pay for it (because not only did you have two copies, so did everyone else).

Thankfully, since then they haven't tried that again. As such, the only way to get the starter cards is to buy the starter; this also means you need two copies of each for a playset (except for Boba/Luke as you get two of their dice).

Star Wars destiny follows the rule of two. You buy two - two player starter, two of each starter, two of each draft pack, to boxes of each expansion so you can play two of every card.

Yes FFG is evil and they are against your good financial judgement.