Well, the sentence could also mean "I will display her/it"... like what a calculator is thinking when it calculates a number.
Does this "Ich werde sie anzeigen" mean that
I will report (something to) her
I will report her (to the police)
"Ich werde sie anzeigen" means "I will report her/them (to the police)". "I will report something to her" translates to "Ich werde ihr etwas berichten/melden".
From what I understood: anzeigen = report to the police. Berichten = report in a newspaper or something of the type.
(Not a german native)
anzeigen -> is it always to the police , or can I anzeigen you to the, for example, teacher (like teacher, teacher, I saw him cheating on the test!) ?
It's always to the police. For someone dobbing you in, you could use "verpetzen" or "verpfeifen".
Er hat mich an den Lehrer verpetzt/verpfiffen = He dobbed me in to the teacher