Feywild (Stormforge Supplement)
From D&D Wiki
Unlike other worlds the Feywild that touches Aerinthia is cut off from the rest of the Feywild. Eladrin sages are unsure of what this means and many seek the answers why and how the Feywild has been altered around Aerinthia. Oddly enough the answer rests all around them for when the fey seek to leave the Aerinthian Feywild they are blocked by the Storm.
One other notable difference in the Aerinthian Feywild is that at the border of Shadar there is a visible impenetrable barrier that surrounds the entire region and no method of by passing the barrier has yet been found. Attempts by Eldarin to feystep or enter the Feywild while within Shadar have always failed and shunted the traveler outside the barrier, regardless of distance traveled across Shadar.
It is unknown at this time how the Feywild is affected throughout the rest of Stormforge.