What are the odds an alien species would be similar to us physiologically

Hmm; I doubt this is correct. A species with a trunk that develops language and a sophisticated civilisation would have an entirely different developmental path to humans, so there is no reason to expect them to pass through every stage that humans did, any more than we would expect to pass through every stage that trunked sapients would.

Obviously a herbivorous sapient would not need to kill prey animals. But they might desire to control the population of other animals, especially if they are in competition with them. Competition and co-operation between individuals in the herd is likely to be the most likely route to linguistic sophistication, so they could use the same strategies to eliminate competitors from other species as well.

These hypothetical trunked sapients could start to use simple tools, such as primitive clubs or hammer stones, as part of their competitive behaviour. Or the trunked species might start to use tools to help them obtain food; elephants have tusks, as well as trunks, which they use in their feeding behaviour.

A trunked species that does not develop tusks might develop tool use as a substitute for these useful implements.

Over time these tool using creatures could evolve ever more dextrous trunks, just as apes became more dextrous over time. On our world the African elephant has evolved an extra digit compared to the Indian elephant.

a highly dextrous trunk could include numerous digits, and even branches. Assuming that the original ancestors had two nostrils, these paired nostrils could easily have a trunk each.

I would expect a herbivorous sapient to use vegetable fibres rather than fur, although they might have a quantity of pelts available if they have eliminated a few other large animals from the environment. They could use their hypothetical dextrous trunks to fashion clothing from these pelts, assuming that their trunks are considerably more capable than those of their less dextrous ancestors, just as our hands are much more dextrous than those of the apes.

Sure; on our world there are many species with quite considerable abstract intelligence, as the

[quote]
Mirror test - Wikipedia]mirror test seems to indicate. Most of these are handicapped by an absence of dextrous limbs. I tend to think that there are many worlds in the universe that hold such handicapped species, and these species will rarely develop civilisations; but give then an appendage, or two, or twelve, and the sky is the limit.

If you know of any old sci-fi movies that include trunked sapient species, I’d be quite interested to hear about them. Most old sci-fi movies use humanoid aliens for a variety of fairly obvious reasons.

As has been pointed out, elephants are used for heavy lifting in some countries. But I think this is limiting the conditions to species which closely resemble elephants too closely. To state the case a little more clearly - there are no elephants on other worlds, so we need not limit our considerations to what elephants can or cannot do.

This generalisation can be expandedinto an astrobiological mantra, which I always like to trot out in threads like this.
There are no elephants on other worlds outside the Earth. There may be organisms that vaguely resemble elephants, but when examined closely they will have some or many significant differences.
There are no humans on other worlds outside the Earth. There may be organisms that vaguely resemble humans, but when examined closely they will have some or many significant differences.
There are no mammals on other worlds outside the Earth. There may be organisms that resemble mammals, but when examined closely they will have some or many significant differences.
There are no animals on other worlds outside the Earth; that is there are no members of the kingdom Animalia. There may be organisms that resemble members of the Earth kingdom Animalia, but when examined closely they will have some or many significant differences.

When considering species on other worlds, we would do well to remember that each species will be entirely unrelated to life on Earth, and will have a completely different ancestry.

Coupled to that is the fact that every planet will present a unique physical environment, we will be lucky to see even the most basic similarities between humanity and intelligent species on those worlds.