There has only ever been a handful of merch found in Hebrew - mainly books, the other ones I can think of which turned up were The Stolen Shadow and The Man in the Moon. They are pretty hard to find though; I only ever remember seeing a couple of versions of each over all the years.
I wouldn't be surprised if most of the merch remained in English, actually. I was in Israel several years ago and the country is trilingual (Hebrew, Arabic, and English). Most signs and advertisements would have all three languages on them. The majority of people know a bit of English due to it being taught in school and many films and TV programs not being translated.
I suspect it was also much cheaper on Hasbro to not translate for a very small distribution area.
If we can find scans of the books or backcards I'd love to see them, though! I'm really curious how they would be formatted as both Hebrew and Arabic are written right-to-left as opposed to left-to-right, like English.