Is it possible to raise WAN PPPoE on the Mikrotik VLAN interface without the participation of the provider?

Question

Computer networks

Good day! A little background for understanding the motives of emerging drug addiction. There is a room of 40 squares in which about 40 hosts with statics live, plus the rest of the dhcp-animals. 7 white wired IP addresses also go there, plus all sorts of modems that I don’t take into account yet. All this is ruled by 5 routers from different manufacturers. 4 isolated subnets with duplicate hosts. In one of the subnets, gateways are statically assigned to the required of the two routers. About 100 ports have been forwarded for this entire zoo. There are pieces of iron to which admin passwords are lost. All of this should function flawlessly 24/7. All this was multiplied by the delivery of working iron with wires from the provider, there was no planning and design in principle.
Goal: one router, one subnet, all the same 7 white IPs with port forwarding according to the old logic and Policy-Based Routing.
I have already asked a question in this direction How to get two MAC addresses on one Mikrotik interface? , several days he dug over it himself - he did not achieve the result. I continue moving in the same direction.
Essence: I can not raise more than one PPPoE connection of one provider on one physical port (MAC address). More ports require finances, and it’s not nice to install another switch from the provider’s switch and make a plug (so it is now) to insert into one device. If all this could be turned off for a couple of days, then I would agree with providers, get all these IPs by adequate means, reconfigure the network and not fool myself or you here. But I need everything gradually, turning off just for a couple of minutes, through trial and error and with the possibility of an instant rollback to a working state.
I plan to allocate a port for each provider in Mikrotik RouterBOARD 962UiGS-5HacT2HnT. It seems like a working way to consider PPPoE on different VLANs. There are a couple of Mikrotik RouterBOARD 750 gathering dust. So, is it possible to accept a provider (without PPPoE) on Mikrotik on one port, perform some magic, send a trunk from another port to the next Mikrotik, on which to raise two PPPoE on different VLANs? And if this magic is possible, then what will it be?)
Thanks in advance for any help!

Answer 1

As it turned out, nothing is impossible, and I managed to give birth to this crutch quite simply, as for me. So, what was done:
Mikrotik RouterBOARD 750, the provider's wire is inserted into port number three. Previously, this wire through the switch looked at two routers with their own PPPoE. Port number three acts as a trunk towards the router itself. Two VLANs were created on the second port - 10 and 20.
Next, a bridge was created in which two created VLANs and a third port were added as ports.
This is the picture that came out in Interface
ALL! This turned out to be enough to perform some manipulations on the next Mikrotik and raise two PPPoE on one physical port.
What was done with Mikrotik RouterBOARD 962UiGS-5HacT2HnT:
The third port of the Mikrotik RouterBOARD 750 connects to the second port of the Mikrotik RouterBOARD 962UiGS-5HacT2HnT. On the second port, VLANs are created - 10 and 20, as on the first Mikrotik. Two bridges are created. One created VLAN is added as a port to each bridge, respectively. This is the decisive moment at which you can assign different MACs. By default, the bridge automatically inherits the MAC of the first enabled port it comes across, roughly speaking, dynamic. You can also assign MAC via winbox or web, but you can disable automatic selection only in the terminal, so

/interface bridge set bridge1 admin-mac=E4:8D:8C:53:17:15 auto-mac=no
/interface bridge set bridge2 admin-mac=E4:8D:8C:53:17:16 auto-mac=no

Next, as usual, we create two PPPoE, but specify bridge1 and bridge2 as interfaces. And, lo and behold, both PPPoEs have risen, my white IP statuses are in the statuses, and my joy tends to infinity))
To summarize, the Mikrotik RouterBOARD 750 is five-port, and I have two providers, one of which has two of my PPPoEs, the other has three. I will launch the first port of this piece of iron in the local area so that it is possible to monitor it with convenience, the second and third to two providers, respectively, and the fourth and fifth already to the central router, where they will be allocated a port. Or maybe it will be possible to somehow play around with VLANs and generally put it on the router with one wire without connecting the providers, but that will be a completely different story. In the meantime, the task has been achieved, it remains to carefully test this crutch under load and you can work on)