This is merely a rumor. It can't be real. The same thing happened in May when it was reported that Maguire was a target for interest from Tottenham and West Ham. This supposed information that Chelsea wants to sign Maguire will never be true, it would eventually fade away.
Such news is impossible. To develop a strong squad, Chelsea's owners and fans would not even consider signing Maguire at this moment. The last player they could think of signing would be Maguire. Instead of Maguire being upset about being fired from the team and having his captaincy removed, Maguire should leave Manchester United as a free agent, just like De Gea did.
Rumors don't always have to be believed but sometimes rumor can be true we don't know what their plan is. If you think Manchester United will let Maguire go as a free agent it was a mistake we have to remember when Manchester United signed Maguire they paid 87 million for it so Manchester should get something for his departure. The market value for Maguire is 20 million imagine they could use it to pay player salaries in a few months.