The issue was that I was indeed running out of pins.
Then go with TPIC6B595 controlling PNP transistor, P-channel MOSFET.
Or as input to UDN2981 or UDN2982 if you can find anyone that still sells them:
Can’t go the TPIC route, it needs 4.5V to 5.5V input, teensy runs off of 3.3V in. Should the NPN route not work?