I want to divide wan_net,lan_net and iptv net in the home ethernet. 2 switches are response to divide vlan, which are tl-sg2016d and tl-sg2008d.
I always use 1 cable cat-6 line of port 1 for single line multiplexing. Port 1 is responsible for the transmission of 3 VLAN. Port 2 is responsible for wan_lan. Port 3 is responsible for iptv. Port 4 and all the remaining ports are responsible for lan network.
1.set 802.1Q VLAN of switches
1.1 set tl-sg2016d

Set wan_net, lan_net, iptv of tl-sg2016d respectively. like pic 1.
1.2 set tl-sg2008d

Set wan_net, lan_net, iptv of tl-sg2008d respectively. like pic 2.
2.modified 802.1Q VLAN PVID to assign vlan tag
2.1 set tl-sg2016d

Assign port 4-16 as VLAN 3(lan_net).Assign port 2 as VLAN 2(wan_net).Assign port 3 as VLAN 4(iptv).Assign port 1 as VLAN 1(default).
2.2 set tl-sg2008d

Assign port 4-8 as VLAN 3(lan_net).Assign port 2 as VLAN 2(wan_net).Assign port 3 as VLAN 4(iptv).Assign port 1 as VLAN 1(default).
3. Other thing about ip address
You can assign a lan_net ip address and gateway to switch to replace ip 10.18.18.251 to manage it in the local network.
reference:
1.https://resource.tp-link.com.cn/pc/docCenter/showDoc?productId=1239&type=USER_MANUAL&id=1734588904915967