The @boardwalk guys with @bob and @gudnuf are sending huge zap splits with Cashu afaik.
A single payment is instant, could you just send n payments and that's it? Thinking of @PABLOF7z's new invention (notice how I avoid the name nutsack), you could send multiple note events with ecash and you should be good.
Can you explain the use case in more detail?
I'd you want to lock to npubs: You can lock as many tokens as you like to as many pubkeys as you like (there is a limit but it's large) with a single swap transaction to the mint.
The locked tokens are then just a bearer assets: send them to as many people as you've locked to.
Currently just holding a balance in cashu but paying out over lightining. The dream is nwc + cashu zaps for massive amd instant splits