Player Vicinity detection can be used in 2D, yes - have you tried it? It's similar to working in 3D, only you'll need a 2D Rigidbody and collider instead of 3D ones.
One caveat that does exist is that the Hotspot Detector must be a child of the character's Sprite Child, so that it is correctly rotated along with the sprite when the character moves around the scene.
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One caveat that does exist is that the Hotspot Detector must be a child of the character's Sprite Child, so that it is correctly rotated along with the sprite when the character moves around the scene.