This might be laborious, but it will result in a hard copy of the texts.
Tip: The screenshot process can vary between android devices, but in most cases, you can take a screenshot by pressing the power and volume down buttons simultaneously.
How to take a screenshot on an android phone or tablet. Like taking photographs, this method is easy to use, but can be tedious if the text messages are long or numerous, since only a single screen’s-worth can be captured at once. Take a screenshot of whatever is displayed on the phone’s screen at that moment. You can send it to clients to do themselves as there is a good video showing how to use it.
It is free to download and around $3 to export a text collection.