It's important to note that the information you're looking for is based on speculation, not confirmed facts.
The first two Percy Jackson movies were based on the first two books in Rick Riordan's series, "The Lightning Thief" and "The Sea of Monsters." While there are more books in the series, there has been no announcement of any further movie plans.
To stay updated on potential news about future Percy Jackson films, it's best to follow Rick Riordan's social media or check reliable entertainment news websites.