Yes, in 'echo 3 true story', 'echo 3' is likely related to the 'true story'. It could be the name or identifier for the events that make up the true story.
To add a filter to a story, start by deciding on the criteria for what you want to include or exclude. Then, you can apply this during the planning and writing process. It could be based on character traits, plot points, or the overall mood.
You can usually find the comic filter option in the settings of the app or software you're using. Just look for something like 'filters' or 'visual effects'.
Well, it depends on what you mean by 'real'. Technically, there are AI-based tools and algorithms that can be applied to manga to achieve filtering or manipulation effects. But their effectiveness and accuracy can vary.
It's hard to give a definite answer. Different comic universes and storylines handle the inclusion of Echo differently. You might want to check popular comic franchises or search online for more detailed information.
In most comic versions, Echo isn't deaf. However, there might be alternate or special story arcs where this could potentially be a trait, but it's not a common characteristic.