Encryption characters (mostly %, but also !<,?´@) occur instead of regular ones in the name of a downloaded dataset in ArcGIS Hub with all the default data formats. If you name your file with characters like "ščřžýíéé", it automatically use encryption and the resulting name does not make any sense. It is probably caused by lack of supported character encoding.
Addition of character encoding like Windows-1250 for latin script (Polish, Czech, Slovak, Hungarian, Slovene, Serbian, Croatian, Bosnian, Romanian and Albanian) could solve the problem.