I'm playing the community patch on hard difficulty. When I played on normal, I noticed the units I face in nodes don't seem to have the +2 bonus to melee/armor. I did a new game on hard difficulty, and the units still don't have the bonus. How do I turn it on? Is this a bug?

I'm assuming you are looking at the original defenders of the node, which should match the node's type (nature summons guarding a nature node).

I did some looking on the wiki, and I don't see any notations about changing/removing the node stat bonus for matching summons.

Are you looking at your creatures or the opposition creatures? Anything summoned into the fight (ex. Phantom Warriors) won't have the node stat bonus applied until they start a round of combat in the node.

i just tried and see the same issue. Looks like a bug? community patch.

Post a save file where this happens and we'll look into it.

I just started two new games under the Community Patch to try it out, and I'm seeing the same thing they reported. First game was Easy, Kali, 11 Life, High Elves, yellow flag, summoned a Guardian Spirit and cast Endurance. Attacked the first node I found, which happened to be a Nature node (one sprite, bunch of bears). Second try was Easy, Kali, 9 Nature, Nature Mastery, Conjurer, High Elves, green flag, summoned a bear and a sprite, sent sprites to attack first node I saw (Nature again, single cockatrice).

If summons get the node stat buff, the buff isn't showing up on the unit card in battle. I checked stats for sprites and war bears both in a node and when I freshly summoned them at my capital and I saw the same values.

Screenshot attached of second attempt. Just to make sure, I had my sprites back up on the first turn and checked again. No change.

Just to make sure, I downloaded the current off-line installer from the downloads section, installed it, and tried it. Same issue.

Confirmed, the first node I entered had no node aura. I'll have to investigate which patch caused this.