The first composition is similar to grade 5132 according to SAE J404, but the Mn is to low; it should be 0.60-0.80. Grade 34Cr4 appears in ISO standards like 4954 and EN standards like EN 10263-4 is equivalent to the 5132 and likewise has a minimum Mn content of 0.60.
The second composition meets the requirements of 10L95 according to SAE J403. C100S acording to EN 10132-4 is a nominally 1% C steel for spring discs, but the maximum S content is 0.035 and there is no Pb. C98D2 according to EN 10016-4 is another ~ 1% C steel for drawn wire, and it is common in Europe to specify something like C98D2 + Pb to make it a "free-machining" version of a standard steel.