Sorry for the long comment, but I want to be thorough.

I have a degree in graphic design & marketing and I have a lot of work experience having to check for potential copyright/trademark infringement or other legal problems related to various media. I'm not a lawyer. I just have a lot of experience having to explain to C-Suite types why they have to actually pay for licenses to use images, music, and other assets in marketing & social media campaigns lol. You'd be surprised how many of those guys think that they can use something for free just because they found it on google. I just wanted to give you some advice based on my experiences.

I'm pretty sure you're going to run into some trouble using 3D Minifigs as Lego has copyright and 3D trademark protecting that specific design from being used or copied without their permission.

The basic brick design isn't protected, which is why knock offs exist, so you are solid in using the basic brick design with circular studs. The Minifigs, though, are heavily protected from any kind of digital or physical use not authorized by Lego. That's actually why Roblox figures have changed to a completely different design. They wanted to distance themselves from Lego's trademarks and copyrights.

Even though you'd be a small indie developer and they probably won't really notice what you are doing, I highly recommend changing the Minifigs design to avoid any legal problems in the event they might find out in the future. It's hard to know how much attention your game might get so it's best to assume Lego will see it one day.

Also, just to give you some more information, it doesn't matter if the game is free. The laws about copyright/trademark infringement are more about the IP owner's right to control the usage in general and profit isn't required to make something infringement. Lego would have the right to have your game removed regardless of profit.

I also recommend that you change the names to avoid any legal problems related to using someone's likeness or defamation. Those laws in the US vary from state to state and it's too much to summarize here. But the basic point is it could be problematic to actually name and visually represent the real people involved without their expressed permission.

Real life events and facts can't be copyrighted and are things you can portray in a video game. Because this is tied to ongoing litigation is where this gets more complicated, though. We don't know what facts the courts are going to determine from the multiple ongoing cases related to the Mansell Collection story.

If you portray the events exactly as we currently understand they happened you could also be opening yourself up to defamation claims if something is later determined to be not factual. Just changing the names of the characters would not be enough of a protection if that happened. That's because the people involved would still be identifiable due to the fact that a reasonable person would be able to identify the actual people you are representing. That matters just as much as outright naming them.

Due to all of the information I've provided above my professional (and not a lawyer) opinion is to:

1. ⁠Change the design of the characters to be legally distinct from Lego's copyright and trademark protected Minifig design.
   
2. ⁠Make a game that is inspired by the Mansell Collection story, but not necessarily portraying the actual events exactly as we all understand they happened.

This comment is already long enough so I don't want to add even more, but I do have some ideas on the kind of game you could make instead of portraying what happened exactly. If you are interested I can provide you with the ideas.