我尝试对ggplotly输出进行一些手动更正:

I tried some manual corrections to the ggplotly output:

library(plotly)
library(tidyverse)

mpg2 <- mpg %>%
  filter(manufacturer %>% as.factor %>% as.numeric<6) %>%
  group_by(manufacturer,model) %>% summarize(hwy=mean(hwy)) %>%
  mutate(model=reorder(model,hwy))

myggplot <- mpg2 %>%  
  ggplot(aes(x=model,y=hwy)) + geom_col() +
  coord_flip() + facet_grid(manufacturer~.,scales="free",space="free") +
  theme(legend.position="none", axis.text.y=element_text(),
        axis.title.y=element_blank(), axis.text.x=element_text(size=12),
        strip.text.y = element_text(angle = 0))

# Set dimensions and margins 
g <- ggplotly(myggplot, height=800, width=1200) %>% 
 layout(autosize=F, margin=list(l=170,r=70,b=50,t=50,pad=10))

# Modify tick labels of Honda bar
g$x$layout$yaxis5$tickvals <- 1:2
g$x$layout$yaxis5$ticktext <- c("civic","")

# Modify widths of Honda and Audi bars
g$x$data[[5]]$width <- g$x$data[[5]]$width/4
g$x$data[[1]]$width <- 3*g$x$data[[1]]$width/4

# Modify positions of facet labels
for (k in seq(2,10,2)) {
  g$x$layout$shapes[[k]]$x1 <- 1.15
}
for (k in 1:6) {
  g$x$layout$annotations[[k]]$xanchor <- "center"
  g$x$layout$annotations[[k]]$x <- 1.0375
}

print(g)

结果比以前更好，但并不完美.
希望它能对您有所帮助.

The result is better than before, but not perfect.
Hope it can help you.