I would like to change the legend name, size and position in cnetplot (from clusterProfiler, DOSE and ReactomePA packages). Let´s use the manual example:

library(clusterProfiler)
data(geneList, package="DOSE")
gene <- names(geneList)[abs(geneList) > 2]
head(gene)
ego <- enrichGO(gene          = gene,
                universe      = names(geneList),
                organism      = "human",
                ont           = "CC",
                pAdjustMethod = "BH",
                pvalueCutoff  = 0.01,
                qvalueCutoff  = 0.05,
                readable      = TRUE)
head(summary(ego))
cnetplot(ego, categorySize="pvalue", foldChange=geneList)

The 'foldChange' parameter is very useful to show a number of quantitative genomic features. How could be the best way to modify its legend like in a normal plot. For example:

legend("top", legend="test", pch=21)

 I would be grateful for some ideas!