Is there an easier way to reserve a block of IP addresses?

I've got a more complex network than probably most, I have home automation / security devices I want in a given IP range of say 192.168.4.100 to 192.168.4.199.

Unfortunately the method for reserving IPs in Eero is very piecemeal. It does make it easier to associate MAC addresses,

What I am actually hoping to be able to do is block them out and manage the IPs from another system (PiHole DNS / Manual addressing...).