Yes, on Teensy 4.0 & 4.1, you can remap to any digital pins, even less than or more than 8 pins if you like.
In Arduino, click File > Examples > OctoWS2811 > Teensy4_PinList to see how.
On Teensy LC & 3.x, OctoWS2811 always uses the fixed set of 8 pins.