Yes, both Samsung A34 5G and Samsung A54 5G have variants that support Dual Nano sim cards. And No, both the Galaxy A34 5G and A54 5G does not support eSim.
The Samsung mid-range A series smartphones also have variants that are a Single Nano sim card.
Samsung A34 5G and A54 5G however come with a caveat alongside its Dual Nano Sim cards support which is that the second sim card space is a shared space.
What does shared space mean? It means you can either use two Nano sim cards or one Nano sim card and an SD card.
The SD card space can accommodate a 1TB external memory. So, if having two sim cards in your smartphone is a must, then I think you should go for the 256GB internal storage options on both of these phones.