https://github.com/btcpayserver/node-btcpayBTCpay has a node.js client, pretty easy to implement, completely open source and has LN support.
DO NOT confuse this with Bitpay, the AML/KYC clusterfuck known for their partnership with Bitmain, which many do, and that's how you end up being put on "a list".
I think that kyc is no problem for a merchant in a legit website. Is this the main problem with bitpay? I saw many people recommending bitpay already.
I know btcpay is very good, but I think bitpay is even older.
There was recent news that bitpay are now going to be enforcing their new KYC and Anti-AML terms, and are calling this new service "BitPay ID", it's only here for larger transactions (3,000 USD+ purchases, or refunds of 1,000 USD+), but I definitely see a future where they keep dropping the limit until all customers are required for use "BitPay ID".
The 2 payment processors I've personally used and recommend are Coinpayments and blockonomics, although only blockonomics is able to instantly send you your funds after a customer finalizes a transaction, while payments are held in the Coinpayments wallets I believe.
Have you looked into other payment processors that accept cryptocurrencies as well as other traditional payment options (Paypal, Credit Card) - this might be better for a site that is more mainstream and less crypto-niche.