In the UK under CAP371 we have ' limits on two crew long range operations'.
This means that sectors over 7 hours are factored and penalise the maximum Flight Duty Period allowable. We can get around this penalty by having a third pilot on the flight deck. There does not need to be any facility for rest in this case and the 'heavy crew' can now work to normal limits.
This bears no relation whatever to ' inflight relief ' with substitute crew having rest in a bunk.
I do not believe you have such a rule in Sweden - certainly not in Denmark where the points system takes no account of whether there are 2 or 3 crew on a two-crew aircraft.
In effect this means that flights operating from England to Cancun in the winter need 3 pilots each way ( unless the returning crew are acclimatised ) whereas to Florida 2 crew can do the job.
Of course then ultra long haul with in flight relief is then another subject which I shall leave to someone more qualified to comment.