Own Gnosis Chain based chain

I am wondering if it is possible te setup own Gnosis Chain like chain using:

  1. If it is possible?
  2. It is possible to set a custom ERC20 token (on this deployed chain) as token for transactions fee?
  3. Does such chain would be supported by blockchain explorers, metamask etc.?
  4. Could we be able to add to such chain an optimistic rollup chains using: