If both power tools are single phase, here's a possible solution.
Acquire a couple of three phase motor starters, maybe from scrap/junk. These have a relay with three contacts, start and stop buttons and provision to wire external start/stops.
In starter 1, wire live through first contact to power the router. For added safety, wire neutral to router through second contact. This give 2-pole isolation.
Wire live through third contact to power the vacuum.
In starter 2, wire live through first contact to power the saw. For added safety, wire neutral to saw through secong contact. Again, this gives 2-pole isolation.
Wire live through third contact and then connect a loop wire between the output of this contact and the output of the third contact in starter 1 (the point where the live to the vacuum is connected). This will mean that the vacuum will run when either starter is energised. The neutral for the vacuum will have to be direct from starter 1 (there are no contacts left to provide it with 2-pole isolation but that is nice to have, not essential).
Delay off for the vacuum is a little more involved. Instead of the third contacts from each starter powering the vacuum directly, you would need to connect them to a slow-to-release relay. Unless this relay had contacts rated to carry the current of the vacuum, you would need to connect this relay to a contactor(or another motor starter used as a contactor/relay).
The benefit of using motor starters is the ability to connect external start/stops. You can put a start button near your working position and more importantly, have a foot switch or knee switch that cuts power to everything.
Pay particular attention to ensuring all metal parts are properly earthed and that the supply is protected by a circuit breaker and preferably an RCD.
Finally, unless you are confident with all this, I would strongly recommend getting someone with electrical experience at least to check what you do /intend to do.
3phase