No, it’s not.
It is blasphemy to say Mary is a “co-redeemer,” when God’s word tells us “there is one God and one mediator between God and men, the man, Christ Jesus.”
Anything that denies that fact and substitutes anything, let alone a fallible sinner for the one and only mediator, is a lie that requires correction.
She’s not a sinner. She was conceived free from original sin, and never committed a sin in her life.
There’s nothing more to discuss here. This has been covered on countless threads, and you have posted countless times over countless weeks, months, and years your rejection of the Catholic teaching on Mary, and your belief that it is blasphemy. There’s nothing new to add. I’m not going to spend the rest of my life arguing back and forth with you about what Catholics, and the Church, really believe about Mary. You might want to spend all day long at this forum saying the same thing over and over again, but I have a job, a family, and a life to see to.
Good night.