Highly interesting. As pr professional, I am happy to share my initial thoughts:

I think there are three main action fields for PR at EA:

1. Monitor and build knowledge, e.g., Who is writing in which way about EA? What are the arguments? How to strengthen or counter them? Who are supporters? Who are potential supporters? How we can we reach them? etc
2. Actively manage reputation of EA, e.g., PR campaigns, crisis communications, media appointments, define overall strategy, etc
3. Support and give guidance to EA ventures and initiatives, e.g., better fundraising through more public visibility, higher acceptance of measures/work of the initiative, improving employer branding through PR etc

Regarding the question ‘agency vs internal solution’:

• If you opt for external support, you don’t build PR knowledge inside the organisation, you don’t make and develop media contacts. At the contrary, you make yourself dependent on the agency.
• A significant and important part of PR is to manage expectations and translate/explain the needs and perspectives of journalists and other external stakeholders to internal stakeholders and vice versa. I expect this to be much more complicated in a decentralised movement. This is something that can’t properly be done from the outside. So you need internal PR professionals for that.
• The cost argument against external agencies is valid. I think it is not the most important one though.
• On the other side, external teams can bring in highly valuable expertise and established contacts quickly. And they are more flexible in terms of being able to increase or decrease PR activities without having to manage internal resources.

The bottomline is, if PR is something EA wants to tackle, external support can make sense for any of the 3 action fields I listed above. I strongly recommend though, to have at least a core team to manage PR (and manage external agencies if deployed) + build knowledge and expertise inside the movement.