Wie es aussieht, hatte er ...
The conjunction wie in the subordinate clause causes the subject-verb inversion in the main clause.
So wie es aussieht, hatte er ...
But how about when so precedes wie? I wonder if it is the adverbial phrase "So wie es aussieht" as a whole (rather than the conjunction wie) that necessitates the subject-verb inversion in this case?
Also, how do these two different phrases differ in meaning, if at all? Is it simply interchangeable?