My take on the direction of a hypothetical third game in the series:

-You play as the Hollow Knight, who has adopted a smaller and more friendly appearance.

-Following the events that led to your meeting with Hornet, you’ve been wandering Hallownest in search of purpose.

-Hornet, still acting as the guardian of the kingdom, advises you to journey beyond Hallownest to find your place in the world now that the Radiance is gone. (The game is set between Hollow Knight and Silksong.)

-Eventually, the Hollow Knight reaches the Vast Desert, where they're captured by a crew of antlion pirates and forced into slavery by their captain.

-Among the slaves is a firefly who takes an interest in the Hollow Knight and reveals that the antlion pirates are currently stationed above a thriving bug state hidden beneath the desert, rich in lifeblood.

-This bug state has no leader. The firefly then proposes a deal: he’ll help the Hollow Knight escape if they agree to help the bug state choose a leader, one capable of uniting the bugs to rise against the antlion pirates. (Think of how SMT games handle different alignments (order, chaos, etc) characters representing different ideals.)

-The Hollow Knight agrees, escaping into the underground bug state to begin a new journey.

I’d really like a trilogy since 1) it would slap 2) we all know that 3 are better than 2. 3)Also I'd really like to know what happened to the Hollow Knight! 

However, I’d love for this trilogy to explore new themes instead of returning to the void or higher beings. So I came up with a more "grounded" adventure. An adventure that focuses on concepts like found family, discovering one’s purpose, and defining who we are beyond the legacy or trauma left behind by our family and origins.