I think Runewars is the closest board game to Wesnoth.

[Zephandrypus]

Runewars is a board game that seems to me to be the closest board game to Wesnoth.

1. First off, the map is made of hexes. You and the other players make the board every game.
2. There are four factions, so four players can play. They are humans, elves, undead, and demons (pretty much orcs).
3. Towns are scattered on the map that give you resources.
4. You have strongholds where you recruit units.
5. There are heroes that do quests and get special items to improve their weapons.
6. The fighting is a combination of luck and strategy. You move a number of units into a space with enemy units. Then you draw a number of cards based on how many units you have. Each card has different damage values.
7. Matches can take forever. A typical game takes 8 hours.

Tis a good game, I recommend you guys look into it.