According to this article https://www.greencarguide.co.uk/green-car-guides/smart-fortwo-ed-cabrio-prime-premium/
So essentially, the Smart EQ is a Twizy with a ‘proper’ car body
More like a Zoe in a different (Smart) body, don't you think?
The chassis is a Renault Twingo, from my understanding Renault and Smart worked closely on the development of the fortwo and forfour.
You are right though the Fortwo is what the next gen Twizy should be!
Smart ED is there since 2006 and it is definitely NOT what Twizy 2.0 should look like. Sorry.