This role is optional, and could also be played by any person in the company who has the necessary training, experience and/or certification about effective use of OKR framework. Use of an OKR Digital Tool may also help in measuring and reporting on OKRs.
In short, OKRs require collaboration across many levels of an organization, from leadership to individual contributors. The key roles involve setting goals, ensuring alignment, tracking progress, providing support, and continuously improving the OKR process.