As Nox_meyer has already written, the requested configuration is certainly possible. The following link provides more information and a possible configuration: https://help.ubnt.com/hc...

Yes, the EdgeRouter X can do link aggregation, but you have to keep in mind that the individual ports are individual interfaces, not (layer 2) switch ports. You can bridge the ports and configure them as you described, but the performance within the VLANs via the router will be worse than if you solve this with a downstream L2 switch.