Just share my success story, maybe help someone:
At first, run on ARM64 device（hAP-AX3) :
/interface veth add address=192.168.91.20/24 comment=phantun gateway=192.168.91.1 name=veth-ph
/interface bridge port add bridge=dockers interface=veth-ph
/ip/route add dst=192.168.200.2/32 gateway=192.168.91.20 comment=phantun
/container add auto-restart-interval=8h cmd="phantun_client --local 0.0.0.0:51820 --remote MY_VPS_ADDR:443 --ipv4-only" comment=Phantun interface=veth-ph logging=yes name=phantun remote-image=xyzvps/phantun root-dir=/usb1-part1/phantun start-on-boot=yes
ARM7 device (RB4011):
/interface veth add address=192.168.91.20/24 comment=Phantun gateway=192.168.91.1 name=veth-ph
/interface bridge port add bridge=dockers interface=veth-ph
/ip/route add dst=192.168.200.2/32 gateway=192.168.91.20 comment=phantun
/container add auto-restart-interval=4h comment=Phantun entrypoint="phantun_client --local 0.0.0.0:51820 --remote MY_VPS_ADDR:443 " interface=veth-ph logging=yes name=phantun remote-image=parallelnetliu/phantun:arm32 root-dir=disk1/phantun start-on-boot=yes
x86_64 device (a J1900 box)：
/interface veth add address=192.168.91.20/24 comment=Phantun gateway=192.168.91.1 name=veth-ph
/interface bridge port add bridge=dockers interface=veth-ph
/ip/route add dst=192.168.200.2/32 gateway=192.168.91.20 comment=phantun
/container add cmd="phantun_client --local 0.0.0.0:51820 --remote MY_VPS_ADDR:443 " interface=veth-ph layer-dir="" logging=yes name=phantun remote-image=xyzvps/phantun4-client:latest root-dir=/usb1-part1/phantun_xyz start-on-boot=yes workdir=/root