What are good ways to earn money in Ultra Sun/Moon?

Question

I'm rather poor in Ultra Moon and I don't feel like grinding the Pokemon League. Whoever answers can include the Pokemon League as an option of it's a good one, but I'd like multiple, easily accessible options (like at least 3).

I've been fishing for Pearls since I'm too lazy to do anything else and I want to know if there's an option that's just as low energy but gives me more money.

Comments

I usually smash the rocks on Poni Coast. They can contain Stardust, Star Pieces, and Comet Shards, and with four rocks per loop, you'll start stacking up items pretty quickly.