既然问题已经澄清，我已经写了一个全新的答案：

您可以在单个正则表达式中执行此操作。我认为它非常防弹，但正如你所看到的，它并不完全不言自明，这就是我对它进行自由评论的原因。希望这是有道理的。

您很幸运 .NET 允许重用命名的捕获组，否则您将不得不分几步执行此操作。

resultString = Regex.Replace(subjectString, 
    @"(?:             # Either match...
     (?<before>       #  (and capture into backref <before>)
      (?=\w*\p{L})    #  (as long as it contains at least one letter):
      \w+             #  one or more alphanumeric characters,
     )                #  (End of capturing group <before>).
     \.               #  then a literal dot,
     (?<after>        #  (now capture again, into backref <after>)
      (?=\w*\p{L})    #  (as long as it contains at least one letter):
      \w+             #  one or more alphanumeric characters.
     )                #  (End of capturing group <after>) and end of match.
    |                 # Or:
     \[               #  Match a literal [
     (?<before>       #  (now capture into backref <before>)
      [^\]]+          #  one or more characters except ]
     )                #  (End of capturing group <before>).
     \]\.\[           #  Match literal ].[
     (?<after>        #  (capture into backref <after>)
      [^\]]+          #  one or more characters except ]
     )                #  (End of capturing group <after>).
     \]               #  Match a literal ]
    )                 # End of alternation. The match is now finished, but
    (?=               # only if the rest of the line matches either...
     [^']*$           #  only non-quote characters
     |                # or
     [^']*'[^']*'     #  contains an even number of quote characters
     [^']*            #  plus any number of non-quote characters
     $                #  until the end of the line.
    )                 # End of the lookahead assertion.", 
    "[${before}|${after}]", RegexOptions.Multiline | RegexOptions.IgnorePatternWhitespace);