Apps related to Odoo its projct features
- project_task_stage_email_reminders: create e-mails rules to automatically send out e-mails based on e-mail templates
- project_timesheet_report: export timesheets for a specific project into a PDF
This module will allow you to set rules on stages so that an automatic reminder is sent after X days for the specific stage.
The rules are accessible from the project main view under the smartbutton 'E-mail reminders':

After clicking on this smartbutton an overview shows up from which you can view, add, modify or delete rules:

Allows you to quickly export timesheets for a given project (or projects) within a date range through a wizard:

This wizard can be accessed either through going to a project it's settings and clicking on "Action" > "Project Timesheets" or through the dedicated menu under Project > Reporting > Project Timesheet Report. Here is a sample printout of a PDF:
