Yes, this can be done. Here is an example of reading in all of the xlsx files in a given directory and merging the two sheets in each file and the content of all of the files into a single data frame.
library(openxlsx)
library(purrr)
FILES <- list.files("~/R/Play", "xlsx$")
ReadSheets <- function(Nm) {
map_dfr(1:2, ~read.xlsx(Nm, sheet = .x))
}
Out <- map_dfr(FILES, ReadSheets)
If all of your files are in one directory and they are the only xlsx files in that directory and they all have 25 sheets, that code should work if you set the correct directory path and change the 1:2 to 1:25.