best soundplay comes from noise cancelling headphones naturally. Neutral EQ/settings and you can hear even the quietest noises across the map.
no EQ will help with soundplay, anyone who claims it does has no idea what he's talking about. This is a gimmick.
you can try using loudness equalization/smart volume, it boosts quiet sound and lowers loud sound, the problem that can rise from this is a lack of distance soundscape, so you rely on sound cues. This is the easiest way for bad/mediocre headphones to perform nearly as good as high end ones.
anyway, you should never rely on sound, it should be more like icing on the cake.