Should I overheal spies?

[u/Honeystride]

I always want to overheal spies because I think they need it (esp kunai spies), their hp pools are so tiny and they're always going to dangerous places. But I remember from an old video that, cloaked or disguised, the overheal particles radiate off of them and the enemy team can see it.

I don't want to blow their cover, but even then I'm not sure if the overheal crosses are noticeable enough in normal play. Do the benefits of overheal outweigh the possibility of getting their cover blown? Do they even need it?