It's a role that's exclusively ceremonial. While the Emperor participates in government, it's to do things like appoint a PM and other officials (but the Empero

It's a role that's exclusively ceremonial. While the Emperor participates in government, it's to do things like appoint a PM and other officials (but the Emperor is compelled to appoint those selected by the legislature), officiate opening/closing type ceremonies, issue honors/awards, participate in soft diplomatic relations, etc. So in a way, the role has some small degree of 'power', but it's 'on rails' so to speak, and in theory doesn't directly impact policymaking or governance.