The elf gift, Mystic Rapport, combines two separate concepts, magic detection and mental telepathy. It is important flavor, but seems better to split the concepts to develop each mechanically.
Here I create two new Elf Gifts, "Magic Instinct" and "Mind Play", as suggestions to replace the one playtest gift, Mystic Rapport. Regarding Mind Play, it becomes two-way telepathic communication.
MAGIC INSTINCT
The elven heritage is born of magic, by magic, and for magic. An elf can sense the presence of magic, as a human can see sights or hear sounds.
Innate Magic. You have proficiency with the Arcana skill. You can use your spellcasting ability instead of Intelligence for any Arcana skill use. You can cast any spell you know, that lacks a costly gp component, by means of words only. You yourself are the spellcasting focus.
Faierie. While concentrating, you sense the presence of magic within 30 feet of you. You can sense its general direction and distance. If the magic effect or item is in line of sight, you see an aura of soft white light around it.
MIND PLAY
Elven children grow up playing with each others minds, inviting playmates, sensing thoughts, and sharing delightful imaginations.
Delight. You have proficiency with the Persuasion skill, Performance skill, or the Insight skill. You can use your spellcasting ability instead of Charisma for Persuasion and Performance and instead of Wisdom for Insight.
Dreaming Minds. You can communicate telepathically with a willing creature within 30 feet. You can send each other emotionally-charged images and sounds. You and the creature must share a language in common to understand any words.
At level 9, you can communicate this way with anyone that is personally known to you and willing.