The Google Doc linked here should give a pretty comprehensive overview of where you can find each form. It has been updated mostly by Reddit users in the years following X and Y's release. It also has a visual to make things simpler -- I took the following image from it.
The maroon colour indicates Meadow form:
Yes, it gets as particular as individual provinces and regions. If you'd like the long-winded version:
- Austria: Vorarlberg
- France: Alsace, Auvergne, Bourgogne, Centre, Champagne-Ardenne, Corse, Franche-Comté, Île-de-France, Haute-Normandie, Languedoc-Roussillon, Limousin, Lorraine, Midi-Pyrénées, Picardie, Poitou-Charente, Provence-Alpes-Côte d'Azur, Rhône-Alpes
- Germany: Baden-Württemberg, Saarland, Rheinland-Pfalz
- Italy: Lombardia, Liguria, Piemonte, Valle d'Aosta
- Spain: Cataluña
- Switzerland: Aargau, Solothurn, Basel-Stadt, Basel-Landschaft, Bern, Luzern, Schaffhausen, Jura, Neuenburg, Freiburg, Zürich, Nidwalden, Obwalden, Zug, Thurgau, Schwyz, St. Gallen, Appenzell Ausserrhoden, Appenzell Innerrhoden, Glarus, Genf, Waadt, Wallis, Tessin, Uri, Graubünden
France and Switzerland are your best bet.