Could we see the live-action debut of Phantasm during Season 3 of Titans? That's certainly one possibility based on a recently unearthed character breakdown.
The Illuminerdi has discovered that a character named "Danny" will be introduced in the third season of the DC Universe series. He's described as "a youth who grew up on the wrong side of the tracks but never lost his belief in heroism. His laid-back persona is balanced by a near genius intellect. He has innate detective skills with a perception of detail that is way beyond his years. Despite his rough upbringing, he’s motivated by the opportunity to do good in the world instead of the dwelling in the pain and tragedy."
While that doesn't sound particularly like Danny Chase/Phantasm from the comics (he's actually a bit of an asshole), that is who The Illuminerdi believe this to be.
Whoever this guy is, "a South East Asian actor aged 18 or older to play a 16-17 year old" is being sought for the role, and he'll be a recurring guest star with an either 7 or 13-episode option for the following seasons.
The Phantasm moniker was also adopted by Andrea Beaumont in the 1993 animated film, Batman: Mask of the Phantasm.
Barring any coronavirus-related delays, the third season of Titans is expected to drop in the Fall of 2020