...I was informed that during upgrade from ISO 9001:2008 to 2015, we need to have
FMEA for QMS processes. Please advise.
This is NOT a requirement. FMEA is a tool that can be used for various processes, but it isn't the only method to meet the new ISO 9001:2015 requirements. You've probably heard the saying from Abraham Maslow "I suppose it is tempting, if the only tool you have is a hammer, to treat everything as if it were a nail." Some people think that FMEA is the tool to use for everything risk-related, but it's not.
The actual requirements of the standard are to identify risks (and opportunities) that need to be addressed, to plan and implement actions to address them, and to evaluate the effectiveness of the actions.
Jen Kirley has posted a "Risk Based Planner"
here that seems like a good tool to use to meet the requirements. You may want to look at it as an alternative to FMEA.