I don't think it is an issue at all. Just posted this in my community section. It is a floating system, and grounds are bonded. So polarity does not matter at all. Here was my post:
Hey everyone. I had a lot of people email me this week about concern over bluetti/goalzero/ecoflow products having a reverse polarity RV plug. I don't think it's a problem at all. There is no exposed case on these units, and it's a floating system. It is only considered "reverse polarity" when using the other receptacles as a reference as to what "hot" and "neutral" is considered. It's alternating current though, so it doesn't matter. What does matter is if the reference potential of grounding conductors across ac outputs is bonded. And after testing this five seconds ago, they are. So I don't see any safety issue either. If the outputs were in parallel to increase capacity (with some way to sync the waveforms), the relative "polarity" of the inverters output would matter. But in this instance, I don't see an issue at all. I also can't imagine how electrical engineers from multiple companies could all be wrong in the same way. It is possible, but highly unlikely. If you disagree with me and the engineers, please explain your reasoning below. I would love to hear your reasoning.