Good question regarding cascading skill replacement via Talents.
For “Ear of the Kind” you need quite a few prequisites, one of those (via “A Modicum of Comfort”) is having Society skill Expertise of 1 (or better) to take the root Talent in the Society Talent tree.
“Sophist” only requires Counsel skill Expertise of 1 (or better) to take the root Talent in the Counsel Talent Tree.
The situation where this kind of cascading replace might apply is given in the “Ear of the King” Talent description:
When attempting to spread a message across a large group of people, or even a region, you can substitute your Society skill for Command.
This is a very distinctive application, not a general substitution of Society for Command.
So you would not be able to actually take the role of a commanding officer, leading a military unit, or so, using “The Ear of the King” Talent.
“Sophist” on the other hand is much less limited:
You may substitute Counsel for Persuade or Society.
That is the most broad substitution use case thinkable. Every Persuade or Society test could be made using the Counsel skill Expertise and Focus, if the character has the “Sophist” Talent.
But in that lies the “solution” to the problem in the opening post.
“Sophist” allows you to substitute Counsel for a Persuade test or a Society test.
“The Ear of the King” allows you to substitute Society for a Command test.
There is NO way, that Counsel would be allowed to cascadingly substitute Counsel for Command.
“The Ear of the King” explicitly states the kind of test it applies to: a Command test.
“Sophist” can NOT be used to substitute Counsel for a Command test, only for Persuade tests and Society tests.
Every Skill substitution works the same: the type of test remains of the type of the original skill.
A Command test remains a Command test (and ONLY Command Talents apply, if the character has any).
You only use the numbers, the rank in Expertise and Focus of the substituting Skill, in case of “The Ear of the King” your ranks in Society Expertise and Focus.
It still is a Command test.
So, you cannot use “Sophist” to substitute Counsel for a Command test at all.