There must be 4 different machines (ROUTER, PXE, PC1, PC2), use ubuntu for the Router and PXE, the two pcs must be in different networks (since the iso will be installed by network), the router must be configured with DHCP to provide ip to these PCs, the PXE must be configured with Static IP, MUST NOT HAVE DNSMASQ, (preferably use Alpine ISO inside pxe to install in the PCS).
I hope it can be done <3