OK, I'm using it exactly like that (with working adblock via wireguard). Here my slightly modified /etc/network on the router/server:
# wg server interface
#
config interface 'wg0'
option proto 'wireguard'
option private_key 'xxx'
option listen_port '51820'
list addresses '192.168.1.100/24'
# client 1
#
config wireguard_wg0
option public_key 'xxx'
option persistent_keepalive '25'
list allowed_ips '192.168.1.10/32'
option description 'mobile_db'
# client 2
#
config wireguard_wg0
option public_key 'xxx'
option persistent_keepalive '25'
list allowed_ips '192.168.1.20/32'
option description 'debian_vm'
[...]
config route
option interface 'wg0'
option target '192.168.1.0'
option netmask '255.255.255.0'
On my android mobile I've only added the local/adblock enabled DNS server under "DNS servers" ... works for me.