I'm not too familiar with magnetism and was wondering if there was a material that would reduce the forces of attraction/repulsion between two magnets and would only reduce magnetic forces directly in between the two magnets.
No, nothing like that.
In magnetism there is no such thing as an insulator in electricity, all non magnetic materials perform substantially as the vacuum.
The only way to reach your goal (but probably this doesn't meet your criteria) is to shield the magnetic field by adding a possibly thin sheet of a ferromagnetic material on top of both magnets: they won't attract much anymore, but they'll be also useless.
You control this by shunting (shorting out) just a part of the field. This is an art form in it self. Using thin strips of material with various saturations and temperature coef is how many magnetic devices are tuned.
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Rust never sleeps
Neither should your protection