I think there’s a free version of Onikakushi-hen, the first arc of Higurashi on the App Store, though I’ve just heard of this and I’m not sure if it’s completely true, but if someone else knows about this with certainty please say, so I say download that and start reading it. Then, if you like Higurashi, buy the Higurashi games. This is a more safe way, cause you might end up not liking Higurashi after buying it, so you’ll be more sure this way. Either way, I’d say you go for Higurashi though, since you say you already own Umineko in so many formats and since you’re reading it already, I’d say give Higurashi a try. But then again, it all depends on whether you’ll like it or not, so I’ll say it would be better to go with the first option I gave you.