Vast topic. Shigeko Nakamura gives 2 savory egg recipes with yuzu: onsen tamago with green yuzu, and omelette with yellow yuzu.
The idea of the grated zest of a yellow yuzu in an omelette served hot is excellent, it is also very good with scrambled eggs and boiled eggs. She uses the juice and zest of yellow yuzu.
The zest of finely grated green yuzu exudes freshness in a cold dachi broth, with deviled eggs or with eggs en gelée. Spanish-style poached eggs (egg flowers: Flor de huevo) are eggs broken into a plastic cooking film and poached in hot water. The folds in the film give the egg a flower shape. The Spanish take out the still-soft egg and serve it generously topped with cream, artichoke cream, cream of every vegetable imaginable. The egg flowers on a potato cream with grated green yuzu zest (add it at the last minute) are a good idea.