Single/multi-currency

I am setting up a solution where all reconciliations are done in single currencies per entity, but where the currencies are not the same across the entities using the solution.

Should I use single- or multi-currency in that case?

The currency conversion will not be required in each recon here, but how about reports and dashboards, would we need a multi-currency bucket to be able to see summarized data in one common currency across several entities for those?