I also verified this behaviour in lab.
The documentation about hyper-v replica says :
When you enable Hyper-V Replica for a specific virtual machine, initial replication creates an identical replica virtual machine on a secondary host server. After that happens, Hyper-V Replica change tracking creates and maintains a log file that captures changes on a virtual machine VHD.
In short, when the initial replication starts it will create a replica virtual machine with identical settings, but after that only the changes made on the virtual hard disk are replicated.
Furthermore, the only way i see to replicate the VM hardware changes like cpu, memory is to Remove Replication on the source hyper v host and delete the replica VM on the destination hyper v host, and then configure replication again.
Documentation about hyper-v replica : https://docs.microsoft.com/en-us/windows-server/virtualization/hyper-v/manage/set-up-hyper-v-replica