Maybe what you're talking about is the concept of this kind of exchange? https://bitcointalk.org/index.php?topic=5460187.0
I still can't imagine whether it will work well and sustainably, the problem is that centralized and decentralized are opposites based on the benefits.
Or do you mean that these two types belong to the same exchange but are separate in their application as Binance used to have a DEX version of the exchange?