In a thread on the HO board on 4-6-4 Hudson models, SteamGene wrote:

Quote from: SteamGene on September 17, 2007, 01:01:11 PM
Now why did C&O stick with Hudson and not call the 4-6-4 the Potomac, James, York, Shenandoah, or New River?  (No, I don't have the answer.)
Gene

I find this an interesting question.  C&O had its own names for the 4-8-4 and 2-8-4, thereby avoiding names with Yankee affiliation. But is that why? If so, why not the 4-6-4 too? Certainly, one can reasonably speculate that the C&O and others used a different name due to distaste for the association with the North: just abut every Southeastern road named the 4-8-4 something different from Northern (and from each other). But on the other hand the Southerners were hardly alone in finding their own names, particularly for the 4-8-4 but also other types.
Maybe "Hudson" had some local connection - a geographic feature, station, or junction along the line, or esteemed person or historical figure associated with the C&O - that outweighed the negative of the name from a Northern road?
I thought it odd that someone at C&O thought to reaname the Berkshire - especially considering the design is essentially the same as its van Swerigen sisters NKP and PM used - and NKP also a Southern road. But then, by the time C&O got the 2-8-4 the van Swerigens had gone bust. Ah, but maybe the same design is a clue - could it be a desire to call something their own, when wartime restrictions otherwise dictated reusing an existing design? (if that was so, I  recall reading the PRR used a C&O design for new power during WW2 because of wartime restrictions on new design)