Eador as a strategic game that have a depth so "shard multiplayer" would be great.
But - it is not so great then I have 2x "nearest provinces" with +9gp/turn, and my friend have only +3 swamps.
Is there are any way to make a balanced map or use a predifined one?

Your friend would get more crystals, would summon more zombies and would clear harder dungeons for more loot than you :)
Matter of experience. Province income is very minor thing.
If you want to get somewhat equal start, you can spend 1-2 days on generating maps and saving good ones.

Now we play exactly same way - start a map, and at first check is it "good" or not. If both players say that the map is good - we will play it. Took about 6 maps before good one.

But some times where are really weird maps.

and try to avoid starts right near the boarder unless everyone looses the same number of nearby territories.

If you look closely, you can just see the outline of the outside boarder edge so you can work out exactly where you are on the map, preferably you want end to end not end to middle or something silly like that.