Adobe Analytics - Is it Possible to Copy Values from One Dimension to Another based on a rule?

Not for historical data, no. For new data, you can use Processing Rules to copy/override the data from one dimension to other.

I believe there is a Data Repair API, but there is a cost associated to using that, so it might not be the best option… 

Historical data is tricky, and unfortunately, there aren’t a lot of options available to you. Classifications is usually the “go to” for fixing historical data, but those only work within the confines of the dimension itself, and if you only have “N/A” there isn’t enough info to create a proper mapping.

As ​@kaush1889 mentioned, in the future, you can use Processing Rules, or just use “Dynamic Variables” in your implementation.

For instance, the “standard” URL that goes to Adobe is sent as “g” in the actual analytics string (AppMeasurement.js)

I capture the URL into an eVar, but rather than capture the entire URL, I use “D=g” in my set variables. This is called a “Dynamic Variable” and instructs Adobe to take the value of “g” (i.e. https://www.mydomain.com/something/something/?cid=12345”) and duplicate it into the specified dimension. On top of this, the query string parameters are not yet truncated by Adobe, and so you will get the full URL with all the params. Duplicating in Processing Rules will also include params, as these are removed by Adobe later in the process.

You can actually use the “D=” notation to duplicate any other value.

While the interface has a “Duplicate” function:

It only allows you to duplicate eVar or prop values, but with the D notation, you can reference things like the page name (D=pageName) or the ECID (D=mid) or the Referrer (D=r), etc.

Looks like the only credible solution is the Data-repair or Analysts take one for the team and update 75% of their segments. 

This is a good use case for us to pitch CJA ._.