participate in, give, award, impart, provide, cause
與 centers on giving or providing something to someone, and by extension participating in a shared action or causing something to happen. The core idea is bestowing or joining in.
與 is thought to combine 舁 (four hands lifting) with 与 (to give), suggesting the act of giving or sharing with uplifted hands. The modern form retains the general structure.
The top 臼 looks like two hands lifting something, and the lower part suggests offering. Picture multiple hands coming together to give an award or share a task.
For ヨ, imagine a group of people saying 'Yo!' as they hand over a gift together: 'Yo!' -> ヨ, and everyone participates in the giving.