We had a Henckels paring knife for thirty years. We used it on hard cheeses, mostly cheddar, Gruyere, and Manchego. Last week, the blade split in half. My sense is that line Henckels has diminished in quality since 1983, so I am not going to replace it. Perhaps you could call this source and ask about their recommendations. I have found them helpful in the past.

Here is a link that might be useful: Fantes cheese implements

On a lark, I purchased a Pampered Chef cheese knife& that little knife works great for all kinds of cheeses! Surprised me totally! For the really hard cheeses, any good & sharp paring knife should be fine.

I bought the Cutco cheese knife and love it.