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.
Years back, we stuffed the crankshaft holes (drilled for balancing) with cork and epoxy on our Yamaha YZ 125's and 250's.
As noted, I did accelerate and cut thru my test log (but the blade is somewhat dull). It still ran as if it wasn't missing the stuffers, but I'll know better testing with a new chain.
In any event, a machine that was going to the "parts bin" was saved (and I learned a bunch about the internals of this machine). Also, I learned this Echo model is the ONLY ONE to use them...
I'll repost with a video, once done.
BTW, this smaller machines, per my customer are used for the "climbers", knocking off smaller limbs, way up.
Partially apart (before cleaning):
Complete re-assembly, took about 45 minutes..