I didn't use myself. but I heard that Wassabi and Samurai Wallets are best for privacy purposes.
Another Option is using Bitcoin Mixers, they work pretty well. but you must choose a reputable mixer for that. I can't name any mixer here because this forum does not allow posting any links of mixers but you can find good mixers list at AltcoinsTalks Forum: https://altcoinstalks.com/
All the Best.