I've made this configuration. Can someone check if this is ok?
/interface wireless
add default-forwarding=no disabled=no mac-address=CE:2D:E0:C9:C6:D1 \
master-interface=wlan1 name=wlan-guest1 security-profile=guest ssid=\
"Guest" wps-mode=disabled
add default-forwarding=no disabled=no mac-address=CE:2D:E0:C9:C6:D2 \
master-interface=wlan2 name=wlan-guest2 security-profile=guest ssid=\
"Guest" wps-mode=disabled
/interface bridge
add fast-forward=no name=bridge-guest
/interface bridge port
add bridge=bridge-guest interface=wlan-guest1
add bridge=bridge-guest interface=wlan-guest2
/ip address
add address=10.5.0.1/28 interface=bridge-guest network=10.5.0.0
/ip pool
add name=dhcp-guest ranges=10.5.0.2-10.5.0.14
/ip dhcp-server
add address-pool=dhcp-guest disabled=no interface=bridge-guest name=dhcp-guest
/ip firewall filter
add action=drop chain=forward comment="Drop tries to reach not WAN from guest WLAN" in-interface=bridge-guest out-interface-list=!WAN