To make the syrup, combine the honey, water, and lime juice in a small saucepan. Bring to a boil, stirring often, then reduce heat and simmer for about 10 minutes (syrup will still be on the thinner side). Remove syrup from heat and cool slightly before serving (you can also make the syrup up to a few days ahead and store in a sealed container in the refrigerator).
For the pancakes, combine the milk and the oats in a bowl and set aside to soak while you prepare the rest of the batter.
In a large bowl, stir together the flour, sugar, baking powder, and salt. In a separate bowl, mix together the eggs, melted butter, and vanilla. Add to the flour mixture, followed by the milk/oat mixture, mixing until well incorporated.
Serve pancakes topped with honey lime syrup and a sprinkle of shredded coconut if desired.