'insulting gesture' is a correct and usable phrase in written English.
You can use it when someone has made a physical action towards another person that is intended to be degrading or disrespectful. For example, "John crossed his arms and shot me an insulting gesture".
The "mano in fica" is still used as a highly insulting gesture.
None of the fighters took a bite or a sip, an insulting gesture.
At one point demonstrators held up their shoes to the screen – an insulting gesture in Arab culture.
Basque officials protested that the medal was an insulting gesture of approval for someone who had persecuted their people.
The Russian Football Union has banned a player for three matches for making an "insulting gesture" towards fans who racially abused him.
In an image that seems horrifying in the Thai cultural context, one of the clips showed the king with clown features painted on his face and an image of feet above his head, an insulting gesture in Thailand.
A new set of "criminal offenses" were put on the books, including such acts as insulting gestures and making mischief.
And, sexual harassment is any unwelcome and non-reciprocal verbal or physical conduct of sexual nature such as insulting gestures, jokes, gifts, or offensive contacts.
"Wilshere was charged by the FA with making an offensive and/or insulting and/or abusive gesture during the fixture between Manchester City and Arsenal at the Etihad Stadium on Saturday 14 December.
Ince accepted a charge given to him by the governing body for using an offensive and/or insulting and/or abusive gesture towards a match official during the Tangerines' Capital One Cup defeat to rivals Preston.
The Football Association charge was for an offensive and/or insulting and/or abusive gesture towards an official in the 24th minute.
