While this may be just fun at the moment, it would be quite surprising for Lawrence to take this hypothetical role on a few levels.
If Lawrence currently or in the future has interest in joining the MCU, pairing back up with Pratt in a comedy heavy franchise like Guardians could be a great fit, especially as She-Groot.
Sure, it would be easy for her, but as one of the biggest female talents in Hollywood right now, hiding her star power with a role like this would be odd.
They look as though they have had a lot of fun together filming and promoting Passengers, including trading hilarious insults with one another.