Texting/Messaging Non-iPhone User When No Cellular Signal?

There were some discussions about this a while back, when technology was not quite as fancy. Wonder if ability may now exist.

I occasionally travel to a location with WiFi, but no cell signal. Can iMessage with WiFi others with iPhones, but sometimes I need to text others who do not have iPhones. Message won't send since no cellular signal. Is there any method, whether a newer iOS feature or app for purchase or online program, where I could text or email on WiFi and someone with an Android or other non-iPhone device would receive it as a text message? (While I could send as an email, some people never check that.) I realize there are some apps like Messenger or others, but I wouldn't know what these third parties have on their phones. Looking for a general solution.)

Appreciate any suggestions.