One major warning is the triggering nature. For readers who have experienced abuse themselves, such fanfiction can bring back painful memories. Also, it might promote a negative view of the character or the overall story world. If not handled carefully, it can seem like glorifying or normalizing abuse, which is completely unacceptable.
Possible warnings for 'xander is abused fanfiction' are numerous. Firstly, it can be psychologically harmful to some readers. Secondly, it might not be suitable for younger audiences who may not be able to handle such complex and disturbing themes. Thirdly, in a community sense, it can create an uncomfortable atmosphere if not properly tagged and warned about. Fanfiction should be a place for creative expression within the bounds of respect and ethics, and this type of fanfiction often treads a fine line in that regard.
Warnings associated with 'xander is abused fanfiction' include emotional distress. Since abuse is a heavy topic, it can cause discomfort, sadness, or anger in readers. Additionally, it may not be in line with the intended spirit of the original work. The original work might be about hope, friendship, and adventure, and this type of fanfiction can deviate from that in a very disturbing way. And from an ethical perspective, it can send the wrong message about how to deal with difficult situations.