I have been looking at this recently as a client came to me from a big four firm and included foreign pensions in their FBAR. The link below also suggests that foreign pensions need to be reported as they are an account:

https://www.goldinglawyers.com/reporting-foreign-pension-plans-fbar-lawyers-international-tax/

I believe that the reference to retirement plan covers 401k plans, SEPs, SIMPLE plans etc. and foreign pension plans do not fall within the IRS definition of retirement plan.

As well as the 8938 and FBAR there should also be a treaty disclosure for any gains on stocks held in a foreign pension plan as they are not included in income.