Learning English is difficult "for me" or "to me"?

Question

Note: This post is not about the choice of "for vs. to" in general, it's about their use in terms of "ability vs. action".

I am not sure whether I understand the post "is difficult for me" vs. "is difficult to me" correctly. I suppose the conclusion of which is that the following one is more natural.

"English is difficult for me".

"English" there is a language which could be considered a kind of ability/capability.

How about "learning English"? Which might be more like a kind of action. Is it still more natural to use "for" than "to"?

"Learning English is difficult for me".

Another wording might be

It's difficult for me to learn English.

I tried Ngram Viewer but got "Ngrams not found".

Answer 1

The words "difficult for" are followed by the complement of the preposition "for", which is a noun phrase of some kind meaning whatever experiences the difficulty.
The words "difficult to" are followed by a verb, which is the action that occasions difficulty.

In this use, the word "to" is not a preposition but, a part of the verb. It is a marker of the "to-infinitival" form of the verb.

This distinction is discussed here:

Pearson-Longman forum "to preposition vs to-infinitive

"If to is followed immediately by a simple verb, it is part of an infinitive. If to is followed by a noun construction, it is a preposition." [emphasis added]