Here’s a discussion of augmented chords. As far as I know, they aren’t coming back anytime soon. If you want to at least notate their existence in a tab, you can use a #5 chord by copying it from the .hkt file linked here, but the piano won’t actually play the #5, just a normal triad.
Also, you can only use that file if you’re a Plus member; I’m pretty sure there are tabs in the public database with the #5 chord, and if you found one you could presumably save it in Hookpad and use it instead, but I have no idea what those tabs are or where to find them. If anybody has a link to one that would be great.
2: Recommended substitutions? - #2 by HertzDevil[quote=“bobstella, post:1, topic:317”]
Second is, are slash chords going to implemented?
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Slash chords have also been discussed (EDIT: here and here), and I think 11no3no5 is under consideration for a future release, though I’m not sure. You can achieve some slash chords using the third inversion of 7th chords, but that’s it.