I think you could be INFj in socionics and INFP in MBTI.
Every time one comes across statements like that, one should become suspicious. Anyone who believes that you can be an INFj in Socionics and an INFP in MBTI, or an INFp in Socionics and an INFJ in MBTI might have incorrect views of both INFjs and INFps.

Once you accept the fact that an INFj corresponds to an INFJ and an INFp corresponds to an INFP, you can start learning more about INFjs by reading MBTI descriptions of INFJs. Likewise you will learn more about INFps by reading descriptions of INFPs. Not every statement in every description is true, but the same goes for socionic descriptions. Just look at the thread INTps versus INTjs and you'll see that there are flaws in the understanding of the real types also in Socionics: oldforumlinkviewtopic.php?t=4408

What one should do is read a lot of different type descriptions from different models critically, and then compare the unified picture one gets by doing that with reality, i.e real life persons whose type one is certain of. If one mistypes any of them one is at risk of ending up with incorrect views of several other types, too.