I don't know if this is a scarce variant,

I don't know if this is a scarce variant of this 5 peseta coin, as I see the star has no date and for information that I have seen the star must have a date, could you please help me

Do you have the link to the Numista page of this coin?

Hello,

The number was likely worn off during circulation.

If the coin was uncirculated, it would have been an error.

Slipstreamed

Do you have the link to the Numista page of this coin?

sure, here N#781

to be honest i dont know what variant is 

As you can see on the coin page, the top year line is for “Illegible date” with a 4% frequency meaning a worn off date is quite common in this coin.  Nothing unusual about it.  It is not considered a variant.