I assume the job is for EU citizens, with relocation assistance available. They phrase this as “we can only relocate candidates who are in the EU”.
GP is here to point that this is a misleading way to phrase it because “EU citizens” isn’t synonymous with “people who live in the EU”, which is insufferably pedantic even by the standards of HN.
It’s the difference between residents and citizens being eligible to apply. Actually, restricting non-resident citizens from applying could violate their rights.