all the bitcoin_forks that i have seen so far had replay protection so you don't have much to worry about. but it is best to always create a new wallet and send all your bitcoins to a new address from that new wallet, then start claiming the forked_coins. because the risk is not just the replay protection or lack thereof, the risk is also from trusting your private key(s) to a new wallet software that the for_coin team provided you with.

i think you are confusing a couple of things with each other.
the "risk" of "double spend" is a risk that the receiver worries about until the transaction is confirmed not the sender because a double spend means as long as the transaction is not confirmed the sender can send the same funds to a different address so the receiver should always wait for at least 1 confirmation.

the replay attack that you mentioned is another thing, it has nothing to do with double spending. it simply means when you spend the coins on one chain (if there were no protection) the same transaction can be broadcast and mined on another chain. the solution is simple, move your bitcoins first to a new address from a new wallet and wait for it to confirm then go to the forked chain and spend the new_coins there to another address (like sending the new fork coin to exchange).