But the required arguments defeat the purpose since you'll need the blockchain to get them :P
That is:
importprunedfunds "rawtransaction" "txoutproof"
Imports funds without rescan. Corresponding address or script must previously be included in wallet. Aimed towards pruned wallets. The end-user is responsible to import additional transactions that subsequently spend the imported outputs or rescan after the point in the blockchain the transaction is included.
Arguments:
1. rawtransaction (string, required) A raw transaction in hex funding an already-existing address in wallet
2. txoutproof (string, required) The hex output from gettxoutproof that contains the transaction
To get the txoutproof, you need to ask someone with "-txindex" to use the command:
gettxoutproof "[\"TXID\"]"
Use that complicated method to import the imported addresses' transactions to your wallet or disable pruning to use rescan.