Feeds, PnL cards and screenshots shorten addresses to something like 7xKq...pump. Type the characters you can see and the Wallet Finder recovers the full address from an index of onchain activity.
It is free, needs no sign-in, and shows each match's exchange or KOL label when one is known.
Yes, with no account.
It searches addresses with onchain activity it has indexed. A brand-new wallet with no activity yet may not be there.
Open it in the explorer, or start a Deep Scan to see its funders and connected wallets.