When the issue is interstellar communications, the minimum requirements are language and the technology to send and receive information between stars.
> Experiments have shown that they can learn human sign language and can use whistles for 2-way human–animal communication. Phoenix and Akeakamai, bottlenose dolphins, understood individual words and basic sentences like "touch the frisbee with your tail and then jump over it" (Herman, Richards, & Wolz 1984). Phoenix learned whistles, and Akeakamai learned sign language. Both dolphins understood the significance of the ordering of tasks in a sentence. [0]
Maybe this definition of sentience is too broad, but it is worth evaluating what you can hope to achieve, by looking at the closest approximation available and what you are achieving there. And in this case, I would say "not much". We know e.g. dolphins have a language and communicate, we can very coarsely decipher it, and they can learn to broadly decipher a language we engineered for them. But the most we are achieving with this communication are party tricks in a circus.
And by “a language like ours”, do you mean English? (The one language that we know you and I both have in common.) Noam Chomsky has spent a career looking for a common deep grammar for all human language, and it turns out that there is not much in common, except at the most fundamental and abstract level. Despite this, there are no human populations divided by having mutually incomprehensible languages, and maybe that is so throughout the galaxy.