There are challenges of crossNTF for L2 on crosschain security and decentralization. Recently, there has been a big increase in attacks on crosschain bridges.
Since a crosschain bridge is a holistic system that connects a source chain with a target chain, the attacks on the crosschain integrity can be on source chain, target chain, or the bridge connecting them. The crosschain security has not been mentioned much and recent crosschain attacks have caught crypto communities attention.
To ensure the crosschain bridges are secure, besides securing source and target chain smart contracts, there should also be a shaking and slashing mechanism to safeguard crosschain assets.
Because the value of NFT are subjective and hard to define, the staking and slashing model might need to re-evaluated.