Personality rights differ wildly between jurisdictions, especially between common-law and civil-law jurisdictions. In general, you have no right to use another person's name or likeness. There is no general exception for non-profit usage. You will have to check your applicable laws for details.
Personality rights have trademark-like aspects, but for natural persons. They also touch on privacy and free speech issues. Questions that arise are:
- Could your usage of this name lead to confusion with the natural person?
- Could your usage of this name be mis-interpreted as an endorsement by the natural person?
- Could your usage of this name somehow be detrimental to the natural person (when weighed against your free speech rights)?
In some jurisdictions, your non-commercial use may weigh in your favour but may be irrelevant in others. The strength of this particular mark (even when obfuscated by swapping letters) probably weighs strongly against your use.
For further clarity, consider these thought experiments, assuming you are creating a video player widget for websites:
Consider an actual trademark like YouTube. Can you name your project TouYoube as a play on that? If not, then the same reasoning would likely apply to personality rights (especially in U.S. jurisdictions).
Consider downstream usage of your project. You name the video player “BenKurns” as a pun on “Ken Burns”. It gets more successful and starts being used on porn sites. Would the use of the name “BenKurns” on porn sites violate the personality rights of Ken Burns? If so, who would have performed the violation, the site or you?
I don't know the “correct” answers for these thought experiments and the answers will of course depend on jurisdictions and specific details of the case. But your proposed usage is raising questions where the answer is not obviously “go ahead, you're fine”.
I would suggest that you avoid celebrity names or puns on these names for open source projects. Quite likely, no one will see your open source project and no one will care. However, you are inviting an unnecessary risk for cease and desist letters.