In fanfiction, the way Spider Man's Tantric Energy works can be a complex and creative concept. Some authors might depict it as an energy that is in harmony with nature, much like how his traditional powers are related to the abilities of a spider. So, when he is in natural surroundings, he can access and utilize the tantric energy more effectively. It could also be that this energy is tied to his emotions, for example, when he feels a strong sense of justice or protectiveness, the tantric energy surges within him, giving him a boost in his powers. This allows the author to add an extra layer of depth to Spider Man's character and his power - using scenarios in the fan - created story.
In some fanfictions, Spider Man's Tantric Energy might work by him having a deeper connection to a spiritual realm. This connection could allow him to draw on the energy for enhanced strength, agility, or even new powers like the ability to sense danger on a more profound level. For example, it could be that he has to meditate or perform certain actions to tap into this energy.