I’ve uploaded the SeaBee Engineer Unit Database file. This is in response Xantam and his request on the official EDCE forum. You can view the post here.
Per the description:
How to Use It:
Engineers won’t be able to move on sea squares unless loaded to the Seabee. When your loaded Seabee reaches the desired sea/shallow tile, use the Drop option to unload the engineer. Once dropped, any valid construction option will be available to you. To re-load an engineer, load him into a transport or, if next to a shore tile move him back onto dry land.
This database is not configured to be understood by the default AI so be warned. Also, pathfinding may cause some issues since engineers can travel over sea tiles.