The Dark Times between Episodes III and IV is part of the Star Wars timeline that is ripe for storytelling and exploration. This happens to be the setting of the currently on-hold Live-Action series. What little we know about the Live-Action series is that it isn’t going to focus on Jedi or the main characters from the movies, but instead will focus on other parts of the Star Wars universe. As a result it seems likely that Ahsoka wouldn’t be planned on appearing in the series, however her surviving the Clone Wars and appearing in the series would certainly help bring some fans from the cartoon to the Live-Action series as they grow up and mature. Even if she was not to be in the Live-Action series, there is always the possibility they could do another cartoon series or use Ahsoka in novels, comics or games in the future.
How exactly could Ahsoka escape Order 66? Ahsoka could pull a Yoda and kill the Clones sent to execute her then go into hiding. Ahsoka could be saved by a friendly clone such as Captain Rex or ARC Trooper Fives. The Clone could desert and go on the run with Ahsoka or could die protecting her while she escaped. One idea that I like is to have someone help Ahsoka escape, perhaps Mon Mothma performs a service for Ahsoka similar to what Bail Organa did for Obi-Wan and Anakin in Episode III.