Is there something wrong with how we've done it on wikipedia:Avon Terrace, York in order to display OSM relation 8378127? We have:
{{maplink |type=line |frame=yes |plain=yes |frame-align=center |frame-lat=-31.888526 |frame-long=116.768437 |zoom=13 |id=Q28225083}}
The data has been linked in both OSM and Wikidata for a few days.