The question should be clarified for improving the answer. From what I can understand you want to compare multi-arm studies so my guess would be that it could be reported using a network meta-analysis framework

https://bookdown.org/MathiasHarrer/Doing_Meta_Analysis_in_R/netwma.html

there are different way to do it but a good start would be netmeta package (https://cran.r-project.org/web/packages/netmeta/index.html).

I still have much to learn about this topic, but from my current understanding, and If I understand the question well, the order of the data may not matter in R. You can use a hierarchical model to account for the relationship between effect sizes within studies. This model separates the variation into within-study and between-study components to provide a more accurate analysis.