It's a very old-fashioned phrase. We mostly use it nowadays in a joking way. 1. This doesn't sound very natural to me. We'd probably say 'If you don't mind' in this case. 2. This is quite a specialised use of the phrase. It has no real meaning here, and just indicates that the speaker thinks it is unreasonable that they have been asked to rewrite something. Both are quite rare examples. This isn't an everyday phrase any more - I wouldn't worry about it, if I were you.

If it pleases me, I will answer you. If it pleases another, they will answer you. All of us are quite pleased. It can mean, in a general sense, "if you WILL it". In fact, you can use "if you will" just as you can use "if you please". Also, do not be put off by "archaic" expressions. All of English is credible for usage. In the USA, the phrase "if you please" is quite common. .