Upon further testing, I am beginning to think that this might be a networking issue, and not one to do with the animation blueprints.
I had previously attached a print to the result of setting crouch, which returned satisfactory outputs of true and false when due. However, attaching it to the event tick instead reveals that when the crouch key is pressed, it quickly undulates back and forth between true and false.
I’m not entirely sure what the cause of this could be, but I am happy to make any progress at all in attempting to find a solution.
Post update:
I have tried to lock input setting to local player only, but it did not yield any change in the results.
Second post update:
I have, hardly fortunately, confirmed that the issue is certainly related to networking. Lowering the client count to one results in expected behaviour.
This is problematic as I have no idea what the solution could be. For the time being, I’ll spend the night watching a few more multiplayer blueprint tutorials in hopes of finding useful information.