Yes, both sentences are correct. 👍 They express a past hypothetical situation (the third conditional). “If we were a little luckier, we could have won the match.” Grammatically acceptable in informal English, but many speakers would prefer “If we had been a little luckier…” because the sentence refers clearly to the past. “If luck had been on our side, we could have been champions.” This one is a classic third conditional and sounds completely natural. So both work, but a slightly more standard version of the first sentence would be: “If we had been a little luckier, we could have won the match.” Good question! 🙂