Featured Application Investigating the effects of observing discussions between social robots. A potential application is the design of social robot behaviors in scenarios where robots provide information via conversations. This study investigated how exposure to changing or reaffirmation opinions in robot conversations influences the impressions of observers and their trust in media. Even though the provided conversational contents include the same amount of information, their order, positive/negative attitudes, and discussion styles change their perceived impressions. We conducted a web survey using video stimuli, where two robots discussed Japan's first state of emergency response to the COVID-19 pandemic. We prepared two patterns of opinion changes to a different side (positive-negative and negative-positive) and two patterns of opinion reaffirmation (positive-positive and negative-negative) with identical information contents; we only modified their order. The experimental results showed that exposure to opinion changes from the positive side (i.e., negative-positive) or positive opinion reaffirmation (positive-positive) effectively provides positive and fair impressions. Exposure to an opinion that became negative (i.e., positive-negative) effectively provided negative and fair impressions, although negative opinion reaffirmation (negative-negative) led to significantly less trust in media.