If I play a hidden Switcheroo and my opponent plays Thrill of the Hunt as a reaction to the same battlefield, does Switcheroo still resolve since it states two mights at the same battlefield?

Switcheroo still resolves, but its swap effect does nothing.

Here's why:

Thrill of the Hunt is a Reaction, so it resolves first (LIFO order). It banishes the targeted unit (sending it to the Banishment zone — a non-board zone) and then plays it to a battlefield as a new game object. That unit is no longer the same object Switcheroo targeted — per Rule 359.3.e.4, a target that leaves a non-board zone and returns is a different object and is no longer legal. Even if Thrill plays it back to the same exact battlefield, it's not the original target anymore.

When Switcheroo resolves, only one of its two targets remains legal. Per Rule 359.3.e.8, the instruction executes with only the valid targets — but Swap (Rule 433) requires increasing one value and decreasing another to reverse them. You can't swap one unit's Might with nothing. The instruction can't be followed, so it's ignored under Rule 359.3.e.6. Switcheroo still resolves as a played spell (triggers like "when you play a spell" still fire), but the Might swap simply doesn't happen.