Alien world of angelic floating telepathic beings is doomed, so they switch minds with humans on Earth

[Sanforddoc]

Read in the 1980s, but could be a lot older. The plot involves friendly but desperate aliens who switch minds with humans to preserve their culture on Earth. The humans who find themselves in these ephemeral bodies are at first thrilled, but then horrified to find that they are doomed. The telepathic aliens find human life on Earth awkward, crude and distasteful, especially the sex. In the alien world, one human male engages in a mating dance with a female alien, during which she hurls an egg to him for safekeeping.
Anyone know the title and author?

 

[Danny McG]

Vague memories of reading this, or a similar story

Was the Alien sun in the early stages of going nova?

 

[Danny McG]

This'll become one of those questions that get resurrected every few years by newbies until someone finally solves it
Annoying me cos I have read it years ago but it didn't impress my mind all that much so no firm memories

 

[Danny McG]

Maybe (maybe) Fire Pattern by Bob Shaw

 

[Danny McG]

This has been annoying me so I've looked on another site.
Two possible answers...

Manta's Gift by Timothy Zahn

Or the most likely..
Up the walls of the world by James Tiptree Jr (Alice thingummy)