I don’t know of any that are particularly easy to get spawning (coral spawns are still actually fairly rare events in the hobby, though the do happen from time to time). I do know that the Horniman Project Coral has some great info on coral spawning, and there are a few hobbyists working on similar projects now. From what I’ve seen, it seems currently that you either need to have excellent conditions for the corals and be lucky, or you need to pretty intensively replicate the environment those corals are found in naturally in order to get them spawning. The Project Coral I referred to above has a great document about how they basically did just that for four Acropora spp. (see the link below).
https://onlinelibrary.wiley.com/doi/full/10.1002/ece3.3538With more research, we might be able to find some less intensive ways to inducing spawning in corals in the future, but, for now, (to my knowledge) we don’t know what exactly is actually needed to induce spawning in corals (i.e. we don’t what the key factors are), so this is the best we can do for now.
https://www.horniman.ac.uk/project/project-coral/https://www.reef2reef.com/threads/cynarina-lacrymalis-spawning-project-setup.899403/