I have a folder with a few strategies in them.

1. How can I make WL to automatically backtest them every midnight?
2. How can I make WL to automatically email me backtest results using my settings in Preferences -> Email Settings

Thanks in advance

1. You can "backtest" every night automatically by running an EOD strategy in the Strategy Monitor with custom Daily Strategy Scheduling (time selection in Strategy Activation Settings).

Alternatively, the Strategy Ranking tool (if you don't close it and lose all strategies) can be used to run a bunch of strategies. However, you'd need an external macro recorder like AutoIT (or other scripting tool) to click "Begin" for you on schedule.

2. No way. Backtest results are produced by Performance Visualizers. Neither SM nor Strategy Ranking execute visualizers. There's no easy solution for that.