Arcane Confluence

You create an invisible connection between yourself and another willing spellcaster, allowing you to temporarily exchange magical knowledge. Once the spell is cast the connection remains regardless of distance. For as long as Arcane confluence is in effect each participant selects two prepared spells and grants them to the other for the duration of the spell. A spell received in this way is treated as prepared and must be cast using the recipient's spell slots.

The maximum spell level that can be exchanged is one level lower than the level at which this spell is cast (e.g., if Arcane Confluence is cast at 5th level, each participant may exchange spells of up to 4th level). If a recipient lacks a spell slot of the required level, they cannot cast the borrowed spell. Cantrips cannot be exchanged.

If either recipient is unconscious or dies, the spell ends. If Arcane Confluence ends whilst a spellcaster is concentrating on a borrowed spell, they lose the spell from their repertoire as normal, but may continue concentrating on the borrowed spell until said spell ends. Arcane Confluence ends if either spellcaster is in a different plane of existence. 

Concentration Transfer
Only one participant needs to concentrate on this spell at a time, both participants may choose who maintains concentration on Arcane Confluence when it is cast. If the participant maintaining the spell loses concentration, the other may use their reaction to take over concentration. If both participants lose concentration during the same round, the spells ends immediately.

At Higher Levels
When you cast this spell using a spell slot of 6th level or higher, the maximum spell level that can be exchanged increases accordingly.