Ollie, you're using the term "chord chart" referring to an actual keyboard chord and comparing it to a guitar tab. There is no kind of piano chord diagram or whatever for keyboard chords that I've ever seen. A keyboard chord is only written two ways, actual music or a chord symbol. If it's a chord symbol it's up to you to figure out the voicing.

I've been a keyboard player for 45 years and I've seen every kind of chord chart there is from big band to fake books to standard two handed printed piano music. They don't show the fingering for chords because chords are simply linear. If your Em7 is for the right hand you simply finger it left to right, thumb on the bottom, pinky on the top. Left hand it's the opposite, pinky on the bottom, thumb on the top. It's solo runs or melody lines that you might need the fingering shown.

It sort of sounds like you're a student wanting to learn piano chords and voicings. Biab is great for that because most of the piano Real Tracks and all of the midi tracks have been transcribed so you can see the actual notes written out as music. This can be displayed on your screen or printed out. Most of the piano chords will use both hands and you can see that.

Bob

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