Finding a devices unknown IP address and subnet

Hey all, I have some manufacturing equipment that needs to get on our network. These basically all came preconfigured with static IP and subnets unknown to me; some may be able to accept DHCP, but I don't know if that's the case for all of them. The PLCs contain a broad array of industrial ethernet switches with which I have zero experience. I need to get into the GUI of these machines and reset the static IP so it can communicate on the VLAN I've created.

My question is: How do I find out what these IP and subnets are that have been statically set on these devices? For all I know, they could be class A, B, or C private addresses.

I was thinking connecting the devices directly to my laptop with an ethernet cable and running a wireshark capture, looking for ARP broadcasts. But wouldn't my laptops NIC need to be set up on the same network as the device it's connecting to, i.e. if the device is on 192.168.0.0/16 network, my laptop would need to be on that subnet as well, in order to even see the broadcast traffic?

Any advice is greatly appreciated.