Let me put it this way: the commonality between socionics and MBTI holds most if you just take "functions" without function-attitudes in both.
The focuses in the IE/function-attitudes/whatever you want to call them have some legitimate differences.

But the spirit of logic/ethics and sensation/intuition seems to be quite similar to MBTI's version.

If one views the function-attitudes less as independent mental processes and more as just the combination of 2 independent scales as Jung did, e.g. viewing introverted thinking types as thinking types with a penchant for introversion, then this question doesn't arise.
But if one purports to select the most fundamental information the extraversion of a process tells you, and call that an IE of its own right (i.e. for example algorithmic/pragmatic logic and Te), all of a sudden you've introduced a lot more specificity and the potential for another system to approach the subject with another focus.