Can't setup the second WAN(WAN2) on OpenWRT 20.02

Installing and Using OpenWrt
1

Hello!

Today upgraded to OpenWrt 21.02.0 r16279-5cc0535800 on Zbtlink ZBT-WG3526 (16M)
and the Switch section is gone(absent) in LuCi interface. And I can't make the lan1 port to MWAN2 and make the MWAN3-based multi-WAN connection, as described in the https://openwrt.org/docs/guide-user/network/wan/multiwan/mwan3

I was read what with DSA something was changed and in LuCi the Switch we can't find now.

And created the VLAN's in /etc/config/network by hand, like this

config interface 'loopback'
	option device 'lo'
	option proto 'static'
	option ipaddr '127.0.0.1'
	option netmask '255.0.0.0'

config globals 'globals'
	option packet_steering '1'
	option ula_prefix 'fdbd:e0bb:74de::/48'

config device
	option type 'bridge'
	option name 'switch0'
	list ports 'lan1'
	list ports 'lan2'
	list ports 'lan3'
	list ports 'lan4'
	list ports 'wan'

config bridge-vlan
	option device 'switch0'
	option vlan '1'
	list ports 'lan1:t'
	list ports 'lan2'
	list ports 'lan3'
	list ports 'lan4'

config bridge-vlan
	option device 'switch0'
	option vlan '2'
	list ports 'lan1:u*'

config bridge-vlan
	option device 'switch0'
	option vlan '3'
	list ports 'wan'

config interface 'lan'
	option device 'switch0.1'
	option proto 'static'
	option netmask '255.255.255.0'
	option ip6assign '60'
	option ipaddr '192.168.3.1'

config interface 'wanb'
	option device 'switch0.2'
	option proto 'dhcp'

config interface 'wan'
	option device 'switch0.3'
	option proto 'dhcp'

config interface 'wan6'
	option device 'switch0.3'
	option proto 'dhcpv6'

The main idea I was find on WRT3200ACM Switch option missing within Luci in OpenWrt 21.02.0-rc1 - #4 by tweek for this config and some information was find on
The WANB appeared as was later on 19.07.8, as you can see on screenshot

Screenshot from 2021-09-23 13-59-01
Screenshot from 2021-09-23 13-59-011599×549 74.5 KB

But, interface still can't work as WAN. And I can't find the proper instructions about the MWAN3 and second WAN interface creation process for new OpenWRT 20.02 with DSA.

I apologize that I make some errors in this config. I need to make WANB from LAN as described on How can I change my router's lan port to wan port? - #4 by lleachii and can't make it right.

If something know how to make this on new OpenWRT 20.02 with DSA - please help!