[out:xml][timeout:3600]; ( relation(1385350)['wikidata'='Q106130642']['wikipedia'='en:European walking route E8']; relation(1485436)['wikidata'='Q707801']['wikipedia'='de:Obergermanisch-Raetischer Limes']; relation(276003)['wikidata'='Q106052363']['wikipedia'='de:Frankenweg']; ); (._;>;); out meta qt;//['wikipedia wikidata mismatch']
[out:xml][timeout:3600]; ( relation(17051387)['wikipedia'='Kirchberg-Tunnel (Bahnstrecke München–Treuchtlingen)']; ); (._;>;); out meta qt;//['malformed wikipedia tag']
[out:xml][timeout:3600]; ( node(6449425585)['information'='board']['wikidata'='Q59286867']; ); (._;>;); out meta qt;//['information board with wikidata tag, not subject:wikidata']
[out:xml][timeout:3600]; ( relation(13892934)['wikidata'='Q1492355']['wikipedia'='de:Gallersbach']; ); (._;>;); out meta qt;//['wikipedia wikidata mismatch - wikipedia points to disambiguation page and wikidata does not']
JOSM Wikipedia plugin
Note to self: online version hosted at https://matkoniecz.github.io/OSM-wikipedia-tag-validator-reports, files are stored at https://github.com/matkoniecz/OSM-wikipedia-tag-validator-reports.