You can use the RR Elimination Volume device to create hazardous zones that eliminate players when they pass through them.
This device is only available to use in a Rocket Racing UEFN island template and will only work when creating Rocket Racing experiences.

When a Rocket Racing Vehicle overlaps the elimination volume, it will be demolished and reset back to the track, the same way as if it fell off the track or crashed.

In this example, the player drives into an invisible elimination volume to the right of the track. This eliminates them and respawns them back on the primary track as if they had crashed.
See Rocket Racing Devices for tips on how to find this device.
There are no options for this device that can be modified.