I recently picked up the Guildmaster's Guide to Ravnica, and I thought the Guild background approach could easily be adapted to Eberron's Dragonmarked Houses. For example, the Dimir Operative background could easily be a member of House Phiarlan or Thuranni without modification. Mechanically the guild backgrounds don't add much, just expanding the spell lists for characters, so depending on class choices that might not be optimal, though with most classes offering a spell option, it could certainly work. The fluff aspect of the Guild descriptions, particularly the Rank and Renown structure and the "View on Other Guilds" sidebars would work well in a future 5E Eberron update.
I'm not entirely satisfied with the Wayfinder's Guide to Eberron's sub-race approach to Dragonmarked characters; I know the Eberron designers have experimented with different approaches to Marks in 5E (Feat based like 3.5E is an obvious alternative) - I'd be curious to see the Ravnica approach applied to Eberron.
I'm not entirely satisfied with the Wayfinder's Guide to Eberron's sub-race approach to Dragonmarked characters; I know the Eberron designers have experimented with different approaches to Marks in 5E (Feat based like 3.5E is an obvious alternative) - I'd be curious to see the Ravnica approach applied to Eberron.