Nope. Traveling through a worm hole would be instant as it basically connects to points directly. A relay however just allows ships to travel at insanely fast speeds in a virtually mass-free corridor, but it still takes time (even if only a few seconds, maybe a minute). The best example of this is at the end of ME3, where the Normandy is seen traveling in the collapsing mass-free corridor for quite a long time.
Nope. Traveling through a worm hole would be instant as it basically connects to points directly. A relay however just allows ships to travel at insanely fast speeds in a virtually mass-free corridor, but it still takes time (even if only a few seconds, maybe a minute). The best example of this is at the end of ME3, where the Normandy is seen traveling in the collapsing mass-free corridor for quite a long time.
Alright thanks 
Alright thanks
Another example is the cinematic at the beginning of the Suicide Mission in ME2 when the Normandy is launched through the Omega 4 Relay and we see Shepard standing on the shaking bridge for a duration of time before the ship emerges from from the relay and Joker has to start avoiding the derelict ships found on the other side.
In Mass Effect, is space travel via mass relays instantaneous? I know that space travel via FTL can take a little while depending on where you want to go to, I just wanna know if it's the same for mass relays.I ask because the answer is gonna impact my fanfic in a way.
It is pretty much instantaneous, probably taking about 10 seconds. The "time" spent traveling is actually from relay to your destination, or from your starting point to the relay.
It might seem otherwise with Joker, but Joker didnt go trough Mass Relay in ME3, he jumped to FTL from Earth (Mass Relay is at the edge of the solar system)
https://www.youtube....h?v=J2QsbFOCeD4
I'm a bit late but here's a little science background if you're interested, OP. It's more to do with FTL in ME than the Mass Relays themselves, but it's an interesting watch if nothing else; hope it helps you out a bit.
Do góry