What would be the most plausible way to travel between stars?

The least speculative answer is a spacecraft that travels below light speed and takes a long time. The distances are enormous, but space is also extremely empty compared with how crowded it can look in diagrams. Asteroids and stars are not packed together like traffic. A ship would still need to track its position, adjust its course, and protect itself from dust and radiation, but it would not need to thread through a constant maze of large objects.

With current physics, anything with mass cannot reach light speed. A very advanced propulsion system could shorten the trip, but even then it might take many years or much longer. That’s less exciting than a shortcut, but it rests on fewer unproven assumptions.

There are two different questions here: how to cross the distance, and how to avoid hazards. The second is probably more manageable. A star system can be mapped, a route can be adjusted, and a ship could slow down before arrival rather than trying to make a high-speed close pass. Tiny particles are a real concern at high speeds, but that is an engineering problem, not evidence that interstellar travel is impossible.

For propulsion, a light sail pushed by a powerful beam is one concept for sending small probes, while larger crewed craft would need a much bigger energy and life-support system. Neither is an established way to transport people between stars. They are ways to discuss the problem without assuming faster-than-light travel.

Wormholes and warp-style ideas are mathematically interesting, but there’s no demonstrated way to make or use one. Some versions require forms of matter or energy that we do not know how to obtain, and it is not clear that the needed conditions could exist in practice. So I’d treat them as speculative possibilities, not the leading explanation for a visit.

Also, advanced intelligence by itself does not provide a known way around the speed-of-light limit. A civilization could be far more capable than ours and still have to deal with travel time, energy, and keeping a spacecraft functioning.