This seems to be a step in the right direction, I installed the Xiaomi Miot Auto integration and during configuration it found my L10s Ultra! However, it failed to add the it as a device due to this error:

Logger: custom_components.xiaomi_miot.vacuum
Source: custom_components/xiaomi_miot/__init__.py:1418
Integration: Xiaomi Miot Auto (documentation, issues)
First occurred: 4:55:37 AM (197 occurrences)
Last logged: 8:11:21 AM
DreameBot L10s Ultra(dreame.vacuum.r2228o): Got MiioException while fetching the state: Unable to discover the device 192.168.133.122, mapping: {'vacuum.status': {'siid': 2, 'piid': 1}, 'vacuum.fault': {'siid': 2, 'piid': 2}, 'vacuum.mode': {'siid': 2, 'piid': 3}, 'silver_ion.silverion_life_time': {'siid': 19, 'piid': 1}, 'silver_ion.silverion_life_level': {'siid': 19, 'piid': 2}, 'mop.mop_life_level': {'siid': 18, 'piid': 1}, 'mop.mop_left_time': {'siid': 18, 'piid': 2}, 'collect_dust.auto_collect': {'siid': 15, 'piid': 1}, 'collect_dust.clean_times': {'siid': 15, 'piid': 2}, 'collect_dust.dust_enable': {'siid': 15, 'piid': 3}, 'collect_dust.dust_status': {'siid': 15, 'piid': 5}, 'clean_logs.first_clean_time': {'siid': 12, 'piid': 1}, 'clean_logs.total_clean_time': {'siid': 12, 'piid': 2}, 'clean_logs.total_clean_times': {'siid': 12, 'piid': 3}, 'clean_logs.total_clean_area': {'siid': 12, 'piid': 4}, 'audio.volume': {'siid': 7, 'piid': 1}, 'audio.voice_packet_id': {'siid': 7, 'piid': 2}, 'audio.voice_change_state': {'siid': 7, 'piid': 3}, 'map.mult_map_state': {'siid': 6, 'piid': 7}, 'map.mult_map_info': {'siid': 6, 'piid': 8}, 'do_not_disturb.enable': {'siid': 5, 'piid': 1}, 'do_not_disturb.start_time': {'siid': 5, 'piid': 2}, 'do_not_disturb.end_time': {'siid': 5, 'piid': 3}, 'vacuum_extend.work_mode': {'siid': 4, 'piid': 1}, 'vacuum_extend.cleaning_time': {'siid': 4, 'piid': 2}, 'vacuum_extend.cleaning_area': {'siid': 4, 'piid': 3}, 'vacuum_extend.cleaning_mode': {'siid': 4, 'piid': 4}, 'vacuum_extend.mop_mode': {'siid': 4, 'piid': 5}, 'vacuum_extend.waterbox_status': {'siid': 4, 'piid': 6}, 'vacuum_extend.task_status': {'siid': 4, 'piid': 7}, 'break_point_restart-4-11': {'siid': 4, 'piid': 11}, 'vacuum_extend.carpet_press': {'siid': 4, 'piid': 12}, 'vacuum_extend.serial_number': {'siid': 4, 'piid': 14}, 'vacuum_extend.clean_rags_tip': {'siid': 4, 'piid': 16}, 'vacuum_extend.keep_sweeper_time': {'siid': 4, 'piid': 17}, 'vacuum_extend.faults': {'siid': 4, 'piid': 18}, 'vacuum_extend.nation_matched': {'siid': 4, 'piid': 19}, 'vacuum_extend.relocation_status': {'siid': 4, 'piid': 20}, 'vacuum_extend.laser_switch': {'siid': 4, 'piid': 21}, 'vacuum_extend.ai_switch': {'siid': 4, 'piid': 22}, 'vacuum_extend.clean_setting': {'siid': 4, 'piid': 23}, 'vacuum_extend.mop_status': {'siid': 4, 'piid': 25}, 'vacuum_extend.custom_enable': {'siid': 4, 'piid': 26}, 'vacuum_extend.child_lock': {'siid': 4, 'piid': 27}, 'vacuum_extend.sensitivity': {'siid': 4, 'piid': 28}, 'vacuum_extend.mop_way': {'siid': 4, 'piid': 29}, 'vacuum_extend.clean_cancel': {'siid': 4, 'piid': 30}, 'carpet_distinguish-4-33': {'siid': 4, 'piid': 33}, 'vacuum_extend.autowash_switch': {'siid': 4, 'piid': 34}, 'vacuum_extend.warn_status': {'siid': 4, 'piid': 35}, 'vacuum_extend.carpet_clean': {'siid': 4, 'piid': 36}, 'auto_add_detergent-4-37': {'siid': 4, 'piid': 37}, 'vacuum_extend.dry_time': {'siid': 4, 'piid': 40}, 'vacuum_extend.nowater_tips': {'siid': 4, 'piid': 41}, 'filter.filter_life_level': {'siid': 11, 'piid': 1}, 'filter.filter_left_time': {'siid': 11, 'piid': 2}, 'brush_left_time-10-1': {'siid': 10, 'piid': 1}, 'brush_life_level-10-2': {'siid': 10, 'piid': 2}, 'brush_cleaner.brush_left_time': {'siid': 9, 'piid': 1}, 'brush_cleaner.brush_life_level': {'siid': 9, 'piid': 2}, 'battery_level': {'siid': 3, 'piid': 1}, 'battery.charging_state': {'siid': 3, 'piid': 2}}, max_properties: 10/62

So I found an explanation that there are sometimes problems discovering devices across subnets, and my L10s is in a different subnet than my Home Assistant. This seems odd to me, though, because Xiaomi Miot Auto saw my L10s and even knew it’s IP address - but perhaps that’s TCP and the problem is that UDP can’t cross subnets? The article says there are 2 ways to possibly overcome the cross-subnet issue: put the devices on the same subnet (currently not an option for me), and “configure IP masquearding on the outgoing routing interface for the subnet where the MI device resides.” With GPT’s help, I tried to add IP Masquerading (which I guess is just NAT), but it’s not working. I’m pretty confident I did it wrong. Can anyone help me configure my pfsense so that my L10s on one subnet can be discovered by Xiaomi Miot Auto on the other subnet?

Thanks, I’ll take a look.