Standalone MLCK generation for I2S
In your schematic the R5 in series with C16 don't serve any purpose. Your loop to the crystal should come from after R5, like this:



Then R5/C16 cause the required phase shift, and form a low-pass filter preventing the oscillator to oscillate at the 3rd or 5th harmonic. Also, connecting the inverter's output directly to the crystal will overdrive it.