I would suggest using a low cost micro controller such as an audrino based system. Interconnect the audrino and the PLC via RS232/RS485.
Have the audrino handle all of the one-wire, I2C, SPI ... communicators. The audrino can handle this stuff fairly easily.
The PLC doesn’t get involved with the bit fiddling but just gets the data it needs from the audrio via the serial interconnect.
Gary D*ckinson