Nothing seems to be off limits anymore because hollywood has declared open season on all potential products and IP's that can be used to create successful film franchises. It's only a matter of time until we get "skittles the movie"( writing an article about that, you should check it out it later). With the Lego movie being a massive commercial and critical success studios are scrambling to replicate the magic by targeting other popular or lesser known toy brands that could become profitable feature films. Megabloks could very well be on their radar and we wouldn't even have a clue. For all we know, they could be securing the rights in the very same amount of time that it takes you to read this.
Megabloks are essentially building blocks and figurine assembly kits that have many similarities to the lego brand, and that minor similarity prompted the people behind Lego to sue the company behind Megabloks for copying their toy design, but the lawsuit was unsuccessful and Megabloks are still on the toy market. If some studio did decide to make a Megabloks movie then there would be very few hurtles that they would have to jump over to secure the rights. The biggest concern about a Megabloks movie would be coming up with an original story that has a well-rounded plot and interesting characters, and the crew behind the film would have to work very hard to distinguish it from the Lego movie, if that's even possible.
You might be thinking that hollywood has gone nuts, and after the intense bidding war for a movie about Emoji's it would be hard to deny it. However,there were many people that thought the Lego movie was an absurd idea and that it would fail miserably, and now many of those same critics actually like the film, crazy right? It's interesting to see how far studios will go to keep their entertainment empires up and running, at the same time you can't help but worry about the future of creativity and originality. Megabloks might not be an original idea but we have to remember that hollywood is in the business of making money, and if Megabloks can become a profitable cash cow then the studios will be happy to milk it for as long as they can.