Question: How are WordPress based agencies and theme development shops preparing to deliver FSE themes?

Answer: Momentum is gathering.

Responses to date:

From Ben Gillbanks, professional theme developer

In terms of how I, as a theme shop, am preparing. I’m not doing much at the moment. I’ve spent some time learning how to build blocks, and now I am waiting for more information on the best practices for building themes. I think the next WordPress release, with the inclusion of FSE will be very interesting and maybe then I can start thinking about FSE themes properly.

From Anne McCarthy, Developer Relations Wrangler.

I’d say

• some folks are starting to hire (https://decubing.com/fse/),
• starting to make changes to their offerings, (https://wptavern.com/genesis-framework-to-become-free-studiopress-announces-changes),
• starting to work on block themes (https://twitter.com/andersnoren/status/1381170358187913220)
• and joining community discussions (https://wptavern.com/universal-wordpress-themes-virtual-hallway-hangout-planned-for-may-14).

From Tom de Visser

I’m working at an agency and we want to build websites that last at least 4-5 years, so we are looking for the right moment to switch to Gutenberg. Not ending up rebuilding hundreds of sites within 1-2 years because it isn’t stable enough, but also not starting too late when the old editor gets deprecated.

From WPMarmite’s 127-Shop Full Site Editing study

From a smaller group of 22 of the 127 theme shops, those that offer custom Gutenberg blocks,

• 86% of these theme shops believe that Full Site Editing is a breakthrough for WordPress users.
• 22% of them are working on a FSE-ready theme.
• Only 9% are contributing to the development of FSE.

For details see Full Site Editing Study: Will WordPress theme shops embrace this new paradigm?

See also WP Tavern’s comments on the study which also digs into the very low number of theme shops providing block patterns ( 3% of 127 ).