Power BI Pro License for each/all different organisations using on-premises Power BI Report Server

I am a Power BI developer and aim to work on various clients' on-premises Power BI Report Servers.

I have a Power BI Pro license bought for consulting purposes for my own personal company.

Questions:

1. May I use my own personal Power BI Pro license bought for my own company with domain www.xyz.com to share published reports with users from different organisations with domains www.client1.com and www.client2.com? Or should I purchase Power BI Pro licenses to share reports for each organisation?
2. Do I need a Power BI Pro License for Development environments? I refer to a previous conversation below, where it states that a Power BI Pro license is required, but I need to make sure of the fact. https://community.powerbi.com/t5/Integrations-with-Files-and/Do-I-need-a-power-Bi-premium-licence-to-embed-power-BI-reports/td-p/214636

Thank you