extract individual panels of facet plot to re-arrange - ggplot2

Question

I would like to rearrange a facet plot with 3 panels to have them fit better in a poster presentation. Currently, I have A over B over C (one column), and it is important to keep B over C.
What I would like is to have a square (2x2) presentation, with A over nothing, and B over C.
Can I either extract the individual panels of the plot, or create a facet with no axes or other graphic (like plotgrid with a NULL panel).

Answer 1

A second option would be the ggh4x package which via facet_manual adds some flexibility to place the panels:
library(ggplot2)
library(ggh4x)
design <- "
AB
#C"
ggplot(mtcars, aes(mpg, disp)) +
geom_point() +
facet_manual(~cyl, design = design)

Answer 2

One approach could be creating separate plots using nest() and map() from {tidyverse} and then using {patchwork} package to align them as we want.
(Since OP didn't provide any data and code, I am using builtin mtcars dataset to show how to do this). Suppose This is the case where we have a facetted plot with 3 panels in a 3 x 1 format.
library(tidyverse)
# 3 x 1 faceted plot
mtcars %>%
ggplot(aes(mpg, disp)) +
geom_point() +
facet_wrap(~cyl, nrow = 3)
Now to match the question, lets suppose panel for cyl 4 is plot A, panel for cyl 6 is plot B and for cyl 8 is plot C.
So to this, we first created a nested dataset with respect to facet variable using group_by(facet_var) %>% nest() and then map the ggplot over the nested data to get plots (gg object) for each nested data.
library(tidyverse)
library(patchwork)
# Say, plotA is cyl 4
# plotB is cyl 6
# plotC is cyl 8
# 2 x 2 facet plot
plot_data <- mtcars %>%
group_by(cyl) %>%
nest() %>%
mutate(
plots = map2(
.x = data,
.y = cyl,
.f = ~ ggplot(data = .x, mapping = aes(mpg, disp)) +
geom_point() +
ggtitle(paste0("cyl is ",.y))
)
)
plot_data
#> # A tibble: 3 × 3
#> # Groups: cyl [3]
#> cyl data plots
#> <dbl> <list> <list>
#> 1 6 <tibble [7 × 10]> <gg>
#> 2 4 <tibble [11 × 10]> <gg>
#> 3 8 <tibble [14 × 10]> <gg>
Then simply align the plots using {patchwork} syntax as we wanted. I have used plot_spacer() to create blank space.
plot_data
plots <- plot_data$plots
plots[[2]] + plots[[1]] + plot_spacer() + plots[[3]] +
plot_annotation(
title = "A 2 X 2 faceted plot"
)