The common practices are:
A. To have a minimum notice period for employees under probation, and a standard notice period for all the confirmed employees; or
B. To have a specific notice period for employees based on the hierarchy/levels/grades, etc. due to their roles and responsibilities. This remains standard across all the departments and is generally framed based on their levels. (for e.g., an employee on the higher level may have 3 months notice period while an employee at the entry-level may have 1 month notice period.)
Industry standards suggest having a framework of grades/levels for the employees in the first place; this helps the employer to structure the roles and responsibilities, pay scale standards, performance, growth levels, etc. Along with this, the notice period can be designed in uniformity across the departments and teams based on the employees in their respective hierarchy.
Introducing different notice periods within the teams without proper structuring may lead to undesirable effects and consequences.