Players can glitch through blocks and into bases using boats. We have tried disabling boats in faction claims but players can still glitch, just place boat at end of the faction claim.

When you're in the boat:

When you exit the boat.

@voodootje0 Look for the plugin fbasics.

How is this an essentialsx issue?

There are (probably) millions of boat glitches in MC right now, this is most likely neither a Factions nor a EssentialsX issue. I don't think that it's within the scope of EssentialsX/Factions to take care of such glitches.