As of Episode 3 on Stealer by the time of this Recommendation

Stealer has some serious Iljimae vibes. Stealer is set in the modern day, and MC isnt quite doing what they do to protect people, but to protect cultural heritage from the ultra wealthy.

Both have a hidden identity that they use to perform their feats
Both have a public identity that is viewed by others as a failure, delinquent, or otherwise undesirable.

Im telling you, if you liked iljimae for the all around feeling of iljimae, you'll probably like Stealer