The following list is not exhaustive. It highlights different types of reforms that states are enacting. A more comprehensive list is available on Wikipedia, though most of the entries are from 2020.
Policing Reform Has Been a Major State Policy Trend in 2021 (4/8/2021)
Pritzker Signs Sweeping Police Reform, Criminal Justice Bill, Despite Opposition from Law Enforcement (Illinois - 2/22/2021)
California to Ban Chokeholds, Independently Review Police Shootings Under Newly Signed Laws (9/30/2020)
Enhance Law Enforcement Integrity (Colorado - June, 2020)
According to the Denver Post, the law bans chokeholds, requires body-worn cameras, eliminates qualified immunity, etc.
Iowa Governor Signs Police Reform Bill that was Passed in One Day (6/12/2020)
Limits chokeholds, bans hiring of police officers convicted of a felony or misconduct, allows attorney general to prosecute officers if their actions resulted in the death of another person.
Safer NY Act (6/12/2020)
This is a package of 10 bills.
New York Governor - Executive Order No. 203: New York State Police Reform and Reinvention Collaborative (6/12/2020)
Requires local police departments to develop reform plans with community input and enshrine them into local law by April 1, 2021 or risk losing state funding.