Plaion makes the 2600+ and 7800+ which do take original cartridges. However, it does sound crazy to me to try to reproduce the Neo Geo rom slots on modern hardware.
Brainstorming for funsies.
A new version of the AES to take original carts isn't out of the question, and would be pretty neat, but the AES is waaaaay more niche and expensive than the Atari 2600 or 7800 where you can get a wide assortment of carts for dirt cheap. The R&D and production costs wouldn't be at all worth it.
Also, generally, the folks who have AES carts now are going to have a working AES console to go with it, or if they're weird, an MVS converter. Unless they're dying for native HDMI support, I don't see anyone bothering.
If they were bonkers enough to make new carts that would work on original hardware, I'm pretty sure they wouldn't do individual game releases. The smarter move would be to bundle multiple games on one cart, e.g. all the Sam Shos or KOFs. That might actually get some traction. But, we live in a world of SD MVS and AES carts now, so if you're nerdy enough to have an AES, then you probably already know about and own one which can play everything for free outside of the cost of the cart and an SD card.