mempool policy/standardness is not consensus code. It just extra rules on top that try to reduce the spam on the p2p network and which transactions you want to keep around in your “ready to accept” queue, aka mempool.

Since there could be more transactions you could fit in your system memory, mempool policy helps make sure you see transactions that have non-spammy things like some reasonable min fee or excessive data carrier sizes (this is the controversial bit, whether its worth maintaining that logic you can hack around anyways)

With or without this core setting you can still give the transaction to a miner directly to mine it, since consensus code doesn’t care about policy.