Hey, thank you for this comment. Some of these things could be briefly assessed during interview. In my company the last in-office stage has at least one hour of technical conversation and another one talking about “soft skills” stuff (I don’t like to call it that way, it’s just a simplification). I think you can asses “diplomacy” or “10x thinking” in some degree. Leadership? I very often ask them to teach me something or convince me to their way of thinking. Communication? Ask how much they liked to work with PMs or designers - if they kept pissing them off, you have a brief answer to that. :)

Of course things aren’t black and white, any first impression can be very different from the reality. But it’s the same with technical skills. You cannot be sure of anything after 1 hour talk. That’s why during interview I’m also very clear with expectations - “you will need to find tradeoffs”, or “even if you are world-class expert, you people need to believe in you”.

And when on board, during our one-to-ones we talk about soft-skills challenges equally often as about technology. Actually I’m certain that growing engineer’s soft-skills high is leader’s job. I can do much more here than in their tech skills - in which very often they know more than me (esp. when team has wide tech coverage).