The MAX9278A and MAX9282A datasheets show 6K as the recommended pull-up to use, if required, on the BWS pin.
Reading through the EC Tables and considering leakage currents, it looks like this should be good for IOVDD=3.3V, but a smaller value should be needed for IOVDD=1.8V. However, the 6K value has been simulated for all IO voltages from 1.7-3.6V, and a lower value is not needed. The maximum leakage current on this pin is specified at 3.6V, it is lower at lower Io voltages, hence there is no need to use a different resistor value for different IOVDD.