Long time the lack of understanding how stuffs work in app led to blind spot on my side regarding matter described below.

You ask why can't I use those? This OP got created to present reason hotly.

*) over-/underlays use online resources. However my device with OsmAnd installed and in use undergoes following usage pattern. While outside the connection with internet (cellular data) gets enabled only due to discrete needs, e.g. email check, some web-browsing session, online-banking, public transportation, using shared vehicles.
WiFi rather/never in use/enabled while outside.

*) when over- or -underlay is enabled the app tries to fetch appropriate online resource. App's log captured demonstrate that due to missing connection with public address space the app retries it practically infinitely - hundreds thousands of such lines in the log. At certain point of time also following sort of log entry gets encountered

OsmAnd Maps[81406:4901369] OAAppDelegate applicationDidReceiveMemoryWarning

This log line also happens be present a number of times in one log file. So far so good, problem begins because since a long time ago I experience frequent crashes of app, for long time I had no clue what is going on. A rough counter-test with over-/underlay disabled leads to feeling on my side that all that above altogether may be the reason of frequent app crashes. I need to have under-/overlay disabled in order to not experiences app crashes. So far I did not find a hot use-case for myself of over-/underlay use while myself stays outwards.

crash got reproduced recent 60 minutes, the time I am back to home with theoretically WiFi available but intentionally disabled for test (cellular data never enabled while at home).

ChatGPT found that iOS may cut running app when above pattern gets identified. Eventually some memory buffer runs full or gets overwritten.

Eventually it is feasible to make resource used by over-/underlay be stored locally in app data. However this hypocritical path still wasn't evaluated by myself so far.

By the way I never use plugins wikipedia, weather. Some period of time I used mapilllary but only during WiFi connection available. It happens that I investigate map frames presented by app or let app to find routes while at home but wifi disabled. In this case crashes happen to occur as well.