PhaseShiftBy90 uses a pair of IIR filters to create a pair of signals that are 90 degrees apart in phase at the given Frequency. So there is virtually no delay (at most 2 samples) through the filter.
You can also use the HilbertTransform to make a 90 degree phase shift. The left channel output is the Input phase-shifted by 90 degrees. The right channel is the Input. Delay through this module is ((numberTaps - 1)/ 2 + 1) samples. The larger the number of taps, the higher the quality of the phase shift (but the more processing time required and the longer the delay time through the module).