There is no official connection
Given that the connections you establish are original traits of both characters, we can assume that Wendy was not given any of these traits, in connection with Sabrina; Sabrina was not created for almost a decade.
I can not find any reference to a connection, in the creation of Sabrina Spellman; yes, they do have similarities, but there does not appear to be any official recognition of any form, connecting Sabrina to Wendy.
One may speculate that Wendy was the influence for Sabrina
I would speculate that if Sabrina was created with influence from Wendy, admitting so would be a very unwise move by the creators. The respective characters are creations of two companies that are very much in competition with each other. When you consider that the character "Sabrina Spellman" has been one of the most (if not, the most) popular characters to come out of the Archie series; she has already had her own live action TV series, and with the actual Archie live action taking off, is slated to get another one.
Even if the creators came out and admitted influence, today, they could be opening themselves up to a very expensive lawsuit; so I do not think we will ever know, for sure. They do not appear to be related, but there is good reason for a lack of evidence to say that they are.
Bonus fact: Wendy is a creation of Harvey comics. Harvey is the name of Sabrina's on-again-off-again love interest, and ultimately, her true love (at least, as far as the TV show went. I only really watched the TV show. Sorry, not sorry.)