Difference between i2c switch and i2c mux
The two chips are NOT the same:

The TCA9544A is an I2C Mux.  An I2C Mux multiplexes any one of N downstream ports to the upstream port (1 to 1).

The TCA9546A is an I2C Switch.  An I2C Switch connects one or more of the N downstream ports to the upstream port (1 to many).

The control registers also differ.