All the methods you listed are possible. Which one is the best really depends on the control you want over the process or whether it's a one off operation or something you want to keep running.
Kafka Streams offers a easy way to flow one topic into another via the DSL
You could do something like (demo code obviously not for production!):
Properties props = new Properties();
props.put(StreamsConfig.APPLICATION_ID_CONFIG, "streams-wordcount");
props.put(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, "localhost:9092");
props.put(ConsumerConfig.AUTO_OFFSET_RESET_CONFIG, "earliest");
final Serde<byte[]> bytesSerdes = Serdes.ByteArray();
final StreamsBuilder builder = new StreamsBuilder();
KStream<byte[], byte[]> input = builder.stream(
"input-topic",
Consumed.with(bytesSerdes, bytesSerdes)
);
input.to("output-topic", Produced.with(bytesSerdes, bytesSerdes));
final KafkaStreams streams = new KafkaStreams(builder.build(), props);
try {
streams.start();
Thread.sleep(60000L);
} catch (Exception e) {
e.printStackTrace();
} finally {
streams.close();
}