This Seeking Tech guide will explain how you can easily get the Stray Elements trophy in Metaphor.
For this to unlock, you need to beat 10 elementas. These are rare enemies that will reward you with a lot of MAG and money when defeated. However, they will run away at the first opportunity.
The fastest way to get this trophy is to stun the elementa and then try to end the fight as quickly as possible. You can try changing to an easier difficulty to make these fights less annoying. If they managed to run away, then they should respawn in the same location again.