Which Enneagram types would you say you associate with which quadras?
Let's say, to expand on my previous example, an INFJ identifies 8 and 5 as their most predominant types. There may be something satisfying to them in the LII descriptions, for example, because the descriptions address the use of Ni and Fe/Fi in a particular way that MBTI doesn't address, that describes their lack of image-consciousness in favor of hard analysis and challenging dissection of ideas. The ILI is more tough-minded than the IEI and the EII. All 3 types- the IEI, EII and ILI are all imaginative, courteous, sensitive/emotional and thoughtful like INFJs. But the INFJ 85x might find it hard to reconcile this critical nature with the charming approach of IEI or the more restrained, 1-ish character of EII.
It's less that I have any specific correlations in mind, and more that I see how a specific MBTI+Enneagram combo might lead one to resonate with an unexpected socionics type more than a stereotypical one, especially if the MBTI+Enneagram combo is non-stereotypical or counter-intuitive.
There is always a choice between saying "the description says X, so if you don't resonate with X, you misunderstand how well the description actually applies to you," or "Ok, well, if that's the case, what would someone of those type combinations look like, and why does that make sense/ not make sense?" The latter response still validates the systems, but doesn't attempt to apply them too rigidly at the risk of curbing someone's ability to honestly explore their particular motivations and traits. After all, the system should serve the individual, and not the other way around.
This doesn't even take into account any instinctual variants, either, which would profoundly effect how different MBTI and Socionics descriptions resonate with people.
If you account for all of the possible Tritype combinations, with wings and instinctual variants, and multiply those by every combination between MBTI types and Socionics subtypes, that produces over 5 million personality variations that people could potentially resonate with, which is a mind-boggling number to produce accurate descriptions for. But as a universal system, it works better as a descriptive language than a categorical system.
For example, if someone said they identified as something extremely odd like an ESFP EII-Ne 5w4, 2w1, 8w7 sp/so; one still has enough information to discuss either why this combination may not be likely, or, if for some strange reason upon meeting the person this combination made sense somehow, you'd have enough descriptive information to understand why. An ESFP/EII combo is very hard for me to imagine, but I don't necessarily want to rule it out as impossible. How can anyone really know for sure?
I am a bit skeptical that there actual objective correlations, because who gets to decide how different is too different when it comes to similar types? But for the sake of argument, can an MBTI NF type only be a feeling Beta or Delta? And if others are possible, is it only if the information elements appear in certain blocks?