Hello,
Generally you could connect multiple sites to the same wallet. By this I mean that it is technically possible to do so. It is true that you can specify rpcauth multiple times. I am not so sure about walletnotify / blocknotify, probably you would have to chain the two curl commands in the same line, like so:
walletnotify=curl -s https://example1.com/wallets/api3/notify/BTC/wallet/%s >/dev/null ; curl -s https://example2.com/wallets/api3/notify/BTC/wallet/%s >/dev/null
Or better yet:
walletnotify=/bin/bash /path/to/walletnotify.sh
and then add all of your curl commands in the shell script file. Do the same for blocknotify.
The main issue with this approach is that you are introducing a centralized point of failure for all of your sites. In case any one is hacked, al the funds from all the sites can be lost.
Instead, I recommend that you go the opposite direction: Instead of having multiple sites per wallet, have less than an entire full wallet for each site.
Set up one wallet for each site, and hold only a fraction of the user balances in the hot wallet. Hold the rest of the funds in a cold wallet, using the Cold Storage feature, and replenish the hot wallets as needed. This is much safer in case of a hack. Generally WordPress can be made very secure, but this is hard, and because of it’s popularity, WordPress as a platform gets targeted a lot, so it’s always possible that your security can be breached. It’s best to be prepared.
with regards