Years back, we stuffed the crankshaft holes (drilled for balancing) with cork and epoxy on our Yamaha YZ 125's and 250's.The big difference will be in the acceleration under load.
So put the next size down bar on it and all will be well.
Never seen one on a chain saw but regularly used in motorcycles.
The competition / sports ( higher power ) engines would have the stuffers in there so could be made from all standard parts rather than a new head or piston.
Yes, they're called arborist saws and are very expensive.