This is where a 8x8 pad MIDI controller comes in handy. I use Maschine Jam for this scenario.
Also see previous related discussions…
Producertech Scaler & Maschine Jam Tutorials - Tutorials - Scaler Plugin - Community Forum
Scaler 2 + Maschine JAM - General Discussion - Scaler Plugin - Community Forum
Pad mode & 64 Pad midi controller - General Discussion - Scaler Plugin - Community Forum
All Chords Live at Once (7x8=56) - Feature Requests - Scaler Plugin - Community Forum