One advantage of working remotely is that it’s now easier to bring in a broader group of participants. You have to do this carefully, though. Don’t start with a list of people you want involved in your brainstorming session. Instead, identify the roles and expertise you want, and then find people who fit that description. Ask your colleagues for recommendations of people you might not know who have relevant expertise. This will help you ensure that the group you bring together is more diverse, bringing a range of different backgrounds and perspectives to the problem-solving task.
So start your brainstorming process by having each person generate potential solutions on their own, or perhaps have them work in small groups to think about possibilities. What you want to avoid is having the entire group start throwing out ideas at one another—which isn’t ideal in a remote environment anyway