You're going to want to add a check similar to:

      *{"${class}::${sub_name}"} = $class->make_accessor(
         $index + $offset,
         $attr_name,
      ) unless defined &{"${class}::${sub_name}"};
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where make_accessor() returns a code-reference for an accessor method that accesses $attr_name which is located at a specific index ($index + $offset) in an array-based object.

The important part is the unless defined part.

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