The Attack on Titan movies can have manga spoilers. This might happen if they want to add more depth or take a different direction. But it's not always the case; some might stick closely to the manga without giving away too much ahead of time.
No. While there are significant losses and deaths throughout the manga, not every character meets their end. The plot is filled with twists and turns that determine the fates of the characters in various ways.
The Attack on Titan manga is indeed done. It wrapped up, bringing an end to a popular and highly engaging series that captured the hearts of many readers.
Overall, the 'Attack on Titan' manga is highly regarded for its dark and gritty themes, as well as its detailed world-building. The art style is also impressive and adds to the immersive experience.
At the moment, there's no clear indication. But you never know. Maybe if there's enough interest and the story has potential for continuation, we could see more.