Hazrat Abu Ishaq says that I have seen Hazrat Amr bin Maymoon gesturing during prayer.

Hazrat Jabir narrates that the Noble Prophet (peace and blessings be upon him) once fell from a horse and struck against the trunk of a date-palm, which caused an injury to his foot. We came to visit him, and he was performing prayer while sitting in a room of Hazrat Aisha (may Allah be pleased with her). We began to pray standing behind him. Then, when we visited him a second time, he was again performing prayer while sitting. We began to follow him in prayer while standing, so he gestured to us to sit down.

Hazrat Aisha (may Allah be pleased with her) narrates that once the Prophet Muhammad (peace and blessings be upon him) became ill, so some of his companions came to visit him. Meanwhile, the time for prayer arrived, so he led them in prayer while sitting. They began to pray standing, so he gestured to them to pray while sitting. Thus, they sat down.

Hazrat Zubair bin Adi says that Ibrahim was asked about making gestures during prayer, so he replied that prayer has its own engagement.