I don't think you need a formal analysis to come to that conclusion.   Covid will have a big hit, certainly, but you would expect it to decrease year by year after a certain point, especially as our ways of treating it improve. Brexit has a similar component in things like staffing, but when it comes to trading and such like, we would expect those consequences to repeat every year. So it is rather like comparing a capital cost with a recurring cost. Given enough time, the recurring cost will always dominate.

Exactly when depends on the initial costs and the recurring cost, and how long the recurring costs continue, but in the absence of any other information you would expect the one with recurring costs to cost more in the long term.