I don’t see anything actually animating your character? There’s no state machine present or montage playing in your screenshots.
You don’t need an authority check on inputs, since they will only happen by the owner. When LeftShift is down → Dash Replicated to Server. That’s all you need. “Run on Server” works even if the host player calls it, so just let clients and hosts use the same node.
In your replication settings, “Min Net Update Frequency” should match the “Net Update Frequency”. This gave me a headache for a WHOLE YEAR because my character would scale down the update rate, then sometimes lag when an opponent would idle and I couldn’t figure out why.
Everything else seems like it should update the Dashing boolean and, assuming Replication Conditions on that variable are normal, work. The Print String nodes only activate on the server.
Relooking over everything, were you intending to have a seperate RPC that was multicast? Like, have it go “Dash Replicate To Server”, then on the server, have a “Multicast To All” afterwards? Because both nodes are replicating to the server which is redundant.