PMI stands for Plus Minus and Interesting. It is a simple technique proposed by Edward de Bono for quickly exploring a situation or an idea in a way which inherently compensates for inherently optimistic or pessimistic perspectives. It is usually applied on an individual basis but it can also be used by groups for the same purpose.
It is a timed technique. The idea is that the individual or group first spends two minutes writing down their thoughts on all the positives that emerge from the idea or situation. Then they spend two minutes writing down all of the corresponding negatives or downsides. Finally they spend one or two minutes writing down interesting perspective or possibilities which fit neither into the positive or negative category.
The timings of two minutes work well for groups and people in a virtual environment, but can be a struggle in a physical group environment. To overcome this, it can be helpful for the group to write post-its where they are sat for each of the time periods and then stick them up en-masse.
The technique is helpful in ensuring that optimism and pessimism are appropriately mitigated and balanced.
You can access templates for PMI here: PowerPoint file  |  PNG image (PMI)  |  PNG image (PMI+)  These are easy to include in a whiteboard for a virtual meeting, but may be just as easy to draw-up in a physical meeting rather than print them out.
Track your progress to ensure the efficacy of this strategy.