Anim Trail Doesn't Show Outside Content Example? 4.20.3

I wanted to add a weapon trail to a sword in my game so I followed this tutorial which is fairly old.

The material set up went smoothly as did creating the trail particle. I then tried adding it to a Trail animation notify and it did not render in Persona or in Game. At first I thought there was something wrong with my particle so I tried adding it as a Timed Particle effect and it displayed clearly (although it obviously did not follow the trail behaviour). I thought there might have been something wrong with my mesh so I made a "SideScrollerExample" project and tried adding it to the animations in there. I got the same behavioural problems where there was no visible particles when it was set to Trail but they were visible when it was set to Timed Particle.

I thought maybe this was because the tutorial was old and it didn’t work in 4.20.3 however when I tried it in the content example it behaved as expected, with the trail clearly following the character’s arm.

Any advice on what might be causing the particle trail not to display in these projects?