SN74AHC1G125: Do we have the buffer for UART and I2C?

UART signal lines are unidirectional, so you can use the SN74AHC1G125, or any other noninverting buffer that has the desired voltage and drive strength.

I²C is bidirectional, so you have to use special devices (depending on what the purpose of the buffer is). See Choosing the Correct I²C Device for New Designs (SLVA787) and Why, When, and How to use I²C Buffers (SCPA054).