Due to an unfortunate (mis-)configuration issue I am having ~100 hosts of which the IPv6/IPv4 (even the IPv6 link-local) addresses are all the same and which for the moment I cannot change. However, all hosts have unique and known MAC addresses and are in the same broadcast domain.
Is it possible to communicate with the hosts individually and simultaneously on the IP-level by crafting the corresponding ethernet frame myself that uses the known MAC address and not a MAC obtained via ARP/…? All (embedded) hosts run a Linux network stack.

Are there wrappers for existing programs like curl that would allow me to even maintain a separate TCP connection with each host allowing me to talk to them via HTTP simultaneously in the given above situation? It seems to me that in theory this should be possible.

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