Yes, I’m using that one with a German ISP (PYUR) that does mere MAC-address-based allow-listing + IPv4-only DHCP.
Here’s the gist of what I did:
# on Turris, switch from PHY to SFP
ln -sf armada-385-turris-omnia-sfp.dtb /boot/dtb
# reset with
#ln -sf armada-385-turris-omnia-phy.dtb /boot/dtb
# needs reboot to take effect
reboot
# check everything works
ethtool -m eth2
# Create interface with static IP 192.168.1.100/24 on eth2
# next, login to ONU SFP's OpenWrt
# the password is hardcoded and the key alg is not considered secure by Fedora
sshpass -p '7sp!lwUBz1' ssh -o KexAlgorithms=+diffie-hellman-group1-sha1 -o HostKeyAlgorithms=+ssh-rsa -o PubkeyAcceptedKeyTypes=+ssh-rsa ONTUSER@192.168.1.10
# set your Turris as gateway
root@SFP:/home/ONTUSER# fw_setenv gatewayip 192.168.1.100
# show ONT serial_number
root@SFP:/home/ONTUSER# onu gtcsng
# errorcode=0 serial_number=PMACXXXXXXXX
# show ONT pw
root@SFP:/home/ONTUSER# onu gtcpg
#errorcode=0 password=0000000000
# show ONT state (should be 5)
root@SFP:/home/ONTUSER# onu ploamsg
#errorcode=0 curr_state=5
See also: FS.com GPON ONU Stick with MAC (GPON-ONU-34-20BI) | Hack GPON
tangential: Maybe a mod can reopen GPON SFP options?