Plot ggplot for layer-specific group on a leaflet map in shiny

Question

I have created a shiny app that renders a leaflet map. This also uses a function to allow the user to toggle between 4 different maps. I would also like to plot a ggplot line plot in the corner of the map specific to each group layer. E.g. when GDP is selected a scatter plot appears in the bottom right corner to show its relationship with happiness. I have tried to research how to do this, but have had no luck. Any suggestions would be greatly appreciated.

I would like for the first group (World Happiness Index) to not show a line plot, but for the subsequent 3 groups to show a unique plot each. For the sake of demonstration I do not mind a random ggplot being rendered.

My code for rendering the leaflet map in the server code is as follows:

  output$map <- renderLeaflet({
    
    map <- worldCountries %>%
      leaflet() %>%
      addTiles() %>%
      setView( lat=10, lng=0 , zoom=2) %>% #sets default map pan
      addPolygons(### happiness #########
                  data = worldCountries,
                  fillColor = ~mypalettewhi(happiness_score), 
                  stroke=TRUE, 
                  fillOpacity = 0.9, 
                  color="white", 
                  weight=0.7,
                  label = mytext,
                  labelOptions = label,
                  highlightOptions = highlight,
                  group = "World Happiness Index"
      ) %>%
      addPolygons(### GDP #################
                  data = worldCountries,
                  fillColor = ~mypalettegdp(gdp), 
                  stroke=TRUE, 
                  fillOpacity = 0.9, 
                  color="black", #black is added as highlight as yellows will blend
                  weight=0.7,
                  label = mytext,
                  labelOptions = label,
                  highlightOptions = highlightgdp,
                  group = "GDP"
      ) %>%
      addPolygons(### population #################
                  data = worldCountries,
                  fillColor = ~mypalettepop(pop_density_log), #log is used to diminish extreme values
                  stroke=TRUE, 
                  fillOpacity = 0.9, 
                  color="white", 
                  weight=0.7,
                  label = mytext,
                  labelOptions = label,
                  highlightOptions = highlight,
                  group = 'Population Density'
      ) %>% 
      addPolygons( ### covid stingency ##############
                   data = worldCountries,
                   fillColor = ~mypalettecovid(avg_covid_score), 
                   stroke=TRUE, 
                   fillOpacity = 0.9, 
                   color="white", 
                   weight=0.7,
                   label = mytext,
                   labelOptions = label,
                   highlightOptions = highlight,
                   group = "Covid-19 Stringency Score"
      ) %>%
      addLayersControl( #controls layers
        baseGroups = c("World Happiness Index", "GDP", "Population Density", "Covid-19 Stringency Score"), #base groups indicates these will be toggled between groups
        options = layersControlOptions(collapsed = FALSE) 
      ) %>%
      addLegend( #happiness legend
        values=~happiness_score, 
        opacity=0.9, 
        title = "World Happiness<br /> Index Score", 
        position = "bottomleft",
        colors = c('#ffffb2', '#fed976', '#feb24c', '#fd8d3c', '#fc4e2a', '#e31a1c', '#b10026'),
        labels = c("Less Happy", "", "", "", "", "", "More Happy"),
        group = "World Happiness Index" #group it belongs to
      ) %>%
      hideGroup(c('World Happiness Index','GDP', 'Population Density', 'Covid-19 Stringency Score')) %>%
      showGroup('World Happiness Index')
  })

My code for the function to toggle the map groups within the server code is:

 #### update legend when the selected layer group changes ######################
  
  observeEvent(input$map_groups, {
    my_map <- leafletProxy("map") %>% clearControls()
    
    if (input$map_groups == 'World Happiness Index'){#### Happiness Legend ####
      my_map <- my_map %>%
        addLegend(
          opacity=0.9, 
          title = "World Happiness<br /> Index Score", 
          position = "bottomleft",
          colors = c('#ffffb2', '#fed976', '#feb24c', '#fd8d3c', '#fc4e2a', '#e31a1c', '#b10026'),
          labels = c("Less Happy", "", "", "", "", "", "More Happy"),
          values = worldCountries$happiness_score
        )
    }else if (input$map_groups == 'GDP'){ #### GDP Legend ####
      my_map <- my_map %>%
        addLegend( 
          opacity=0.9, 
          title = "GDP per Capita (US$)", 
          position = "bottomleft",
          colors = c('#ffffd3', '#d9f0a3', '#addd8e', '#7bce7c', '#41ab5d', '#238443', '#005a32'),
          labels = c("Lower GDP", "", "", "", "", "", "Greater GDP"),
          values = worldCountries$gdp
        )
      
    }else if (input$map_groups == 'Population Density'){
      my_map <- my_map %>%
        addLegend( #### pop density legend ####
                   opacity=0.9, 
                   title = "Population Density<br />  (per km\u00B2)", 
                   position = "bottomleft",
                   colors = c('#f2f0f7', '#dadaeb', '#bcbddc', '#9e9ac8', '#807dba', '#6a51a3', '#4a1486'),
                   labels = c("Less Dense", "", "", "", "", "", "More Dense"),
                   values = worldCountries$pop_density_log
        )
    }else{
      my_map <- my_map %>%
        addLegend( #code for covid legend
          opacity=0.9, 
          title = "Covid-19 Stringency Score", 
          position = "bottomleft",
          colors = c('#eff3ff', '#c6dbef', '#9ecae1', '#6baed6', '#4292c6', '#2171b5', '#084594'),
          labels = c("Less Stringent ", "", "", "", "", "", "More Stringent"),
          values = worldCountries$avg_covid_score
        )
    }
  })

My map currently looks like so: