DiagrammeR - Digraph flowchart - Position and direction of labels on arrows

Question

I am making a flowchart using DiagrammeR. I managed to make the nods and label the arrows, but I'd like to be able to decide if the arrow labels will be on the right or left of the arrow. Also, I'd like the arrows to hve diagonal direction, following the arrow. Is this possible?

My code looks like this:

#Dummy data
a<-40
b<-25
d<-15
e<-7
f<-8

#Create fluxogram
grViz(diagram = "digraph flowchart {
  node [fontname = arial, shape = oval]
  1 [label = '@@1'] #total
  node [color = lightblue, style = filled]
  2 [label = '@@2'] #A0
  node [color = grey, style = filled]
  3 [label = '@@3']
  node [color = lightblue, style = filled]
  4 [label = '@@4']
  5 [label = '@@5']
  
  1->2 [label=One_Goes_To_Number_2];
  1->3 [label=oneto3];
  3->4 [label=threeto4];
  3->5 [label=threeto5]
}
  
")

And it returns this:

Flowchart with horizontal misplaced labels

Can I better place the arrow labels?

Also, can I use spaces in the labels? When I try it just breaks.

Thanks!