What does mto stand for in txt language?

"MTO" doesn't have a commonly accepted meaning in text language. It could potentially be a made-up acronym or abbreviation used in a specific context.

To figure out what "MTO" means in a particular message, you'd need more information, like:

* The context of the message: What was the conversation about?

* Who sent the message: Do you know the sender's usual language and abbreviations?

Without more information, it's impossible to say what "MTO" means in your specific case.