As reported in https://github.com/chamard/wikidata_translation/blob/master/GET_DATA.ipynb, some properties with a very long history of edits (especially edits by bots.) take a very long time to load. In some cases, there are no results. For e.g., the translation path of property P255 doesn't show any results using current SPARQL query on WDProp: https://tools.wmflabs.org/wdprop/path.html?property=P225.