In general - yes, it is possible, we have assigning rules in Supplier invoice workflow based on account and code parts. Please note however, that it might be difficult to add “specific person” to a routing path - in fact we will have two routings - one for specific account (with higher priority of the assigning rule) and one for remaining cases - without this person an with lower priority. Question is - how many routing rules do you need? In my current installation, we are using separate approval path for each project (with project cost controller involved), and it leads to more than thousand routing rules...