The Brief: Right in the feels means "emotionally impactful."
If something hits someone right in the feels, then it packs an emotional punch. Such instances usually occur when something is relatable on a deep level. Whereas phrases such as big mood or that feeling when are a bit tongue-in-cheek, right in the feels is reserved for more somber or genuine occasions.
When Khalid says "maybe you weren't the one for me but deep down I wanted you to be" hits me right in the feels..
— Instant Turn Ons™ (@InstantTurnOn) February 16, 2019
This song hits right in the feels!
— Vicky Luminiq (@VLuminiq) February 12, 2019