I believe before N&W received their "Red Bird" GP9's for passenger service they leased a few RF&P E8's. Of course when the GP9's arrived the E8's went back to the RF&P. Other than that there were no more passenger E's until the merger with the Wabash.
The Virginian electric operation only lasted a few years after the N&W merger. The Virginian EL-2b's had N&W road numbers added to the outside of the engines, but otherwise were not repainted before they were retired.
The EL-C's likewise had N&W road numbers added to the cabs. Only one EL-C was repainted to N&W because it was involved in a wreck. Otherwise no paint changes before the EL-C's were sold to the New Haven.
The Virginian FM Trainmasters and Baby Trainmasters were gradually painted N&W.
Ken