Why is the TMCx-HB not listed on the U12 data sheet? Can I use it with the U12 data loggers?

The TMCx-HB temperature sensors have a higher accuracy than the TMCx-HA when used with the H8s because they operate over a narrower range (i.e., accuracy is gained through improved resolution only). Because the U12s provide much better resolution (16X) over the wider range, there is no real accuracy gain by limiting the range.