While it is possible to sign a Universal Binary (Apple Silicon/Intel) VST/VST3 on my Big Sur Intel Mac (latest Xcode), it is not possible to do that on an ARM Mac.
Invalid or unsupported format for signature
That means that it is not possible to generate native VST3 for ARM Macs on a ARM Mac itself, because every code needs to be signed to run natively on ARM Macs.
What are your thoughts, can the problem be solved? Or have I missed something?