We stayed at YC as runners for the Princess Half weekend this year (ran both the 10k on Saturday and the Half Marathon on Sunday). For somewhat related reference, I was at BWI during the Princess Half weekend in 2018 (didn't run that year).
With the caveat that sometimes courses can change year-to-year, the only potentially 'disruptive' impact to the Crescent Lake resorts in my opinion is the 10k run on Saturday morning. Below is the 2019 course map for the 10k - as you can see it exits out the Epcot IG, runners then make the "loop" around the BWI/Swolphin/YC/BC loop. Thousands of runners running on the BWI Boardwalk definitely makes some noise - I had a Boardwalk facing room when I was there in 2018 and it's hard to avoid the noise.
Things are less noisy / less intrusive on the YC/BC side of things as the path is further from the buildings and you don't have the boardwalk/wood planks making noise (other than the small portion in front of YC, but those are a different kind of boards that don't make as much noise when run on).
We were in an early corral so were back in our room at YC while the race was still going on - watched from our balcony as the balloon ladies (the end of the race) came by - photo time stamp of 7:53am. Shortly thereafter things are picked up and it's as if nothing happened.
So, still plenty of time to get to Epcot for a 9am opening. If you're trying to get around Crescent Lake before then, the course may get in your way.
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The Half Marathon on Sunday starts/ends at Epcot, but doesn't go around Crescent Lake or to DHS, so is pretty much a non-issue if you're heading to Epcot via IG. This race is obviously longer and does bleed a bit into park time, but the course enters Epcot more towards the front of the park.
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Again, course maps can change so keep an eye on it when it comes out closer to the event. I suspect it will be similar, but who knows with pending Epcot construction and such.
Note that the Half Marathon on Sunday can cause delays getting to other destinations around WDW - particularly MK as the course uses a long stretch of World Drive, the MK Bus Plaza, etc - so there are several detours for guests heading to MK until things clear up.
Hope that helps!