return arr.map(ele => await axis.get(ele));

is not legal - the await has no corresponding async. You may have wanted to write

    return arr.map(async ele => await axis.get(ele));

but that's the same as

    return arr.map(ele => axis.get(ele));

(Assuming axis.get returns a promise.)

That is, it returns an array of promises of values, not a promise of an array of values like erlich's function.

erlich's example is correct, with the replacement of for-in with for-of.

Edit:

Also, a solution using Array.map() is not impossible:

    return Promise.all(arr.map(ele => axis.get(ele)));

but this has different characteristics than the original function. The original ran the tasks in series whereas this runs them in parallel.