In OSPF, one side MTU is 1500 and another side MTU is 1600. Does it affect neighbourship?

The Neighborship will be formed but it will not form FULL Adjecency. DBD exchange might not happen and the neighborship will be stuck in “EXSTART / EXCHANGE” state.

You can configure OSPF to ignore MTU checking by issuing “ip ospf mtu-ignore” on any one side.