Hi Pawel,
Maps component supports rendering online maps such as Azure
maps, Bings maps and so on via their tile server URLs. The tile server URLs
must follow the below format to render in the Maps component.
https://< domain_name
>/maps/basic/{z}/{x}/{y}.png
”zoom” - It represents zoom factor (level).
”x” - It indicates tile image x-position (tileX).
”y” - It indicates tile image y-position (tileY).
To know more about the online maps in Maps component, please
follow the below UG documentation link.
https://blazor.syncfusion.com/documentation/maps/providers/other-maps
To support localization for the OpenStreetMap, you need to
set the tile server URL that supports localization parameters must be set in
the “UrlTemplate” property of the Maps component.
For demonstration, we found a tile server URL (from a UG
document) as shown below which supports the English language for all the
labels.
https://maptiles.p.rapidapi.com/en/map/v1/zoom/x/y.png?rapidapi-key=YOUR-KEY
NOTE: You need to add the subscription key to use the
above URL.
Please find the screenshot below for your reference.

Similarly, you can check with OpenStreetMap team for their
English localized map and set it in the Blazor Maps component
Please let us know if
you need any further assistance.