The only idea ever conceived for a variant based on the E-100 was a Sturmgeschutz as it turned out the turretring for the large gun required wasn't acheivable.
This idea never made it beyond the conception stage. Also, the E-100 is just a case study, NOT a tank intended for production. As were ALL E-series designs, they were nothing more than designs, case studies and ideas.
For instance the E-10 was ditched in favor of the Pz 38(d), the Germanized version of the Pz 38(t). The E-5 APC was replaced by the Katzchen program.
Anything the E-series studies would produce that looked like it presented a benefit, would be entered into existing Panzer-programme.