You can create your own screen (filter) using the Crypto Screener, save it and set up an alert to create a signal. 

Beware of which time interval you’re working with.  When you create an alert, it will work with that specific time interval only.  So if you wanna be notified of Pairs with a EMA (10) / EMA (20) crossover on 1h time interval, make sure you select that interval.  You will then receive an hourly update with results for your screen.

Tutorials for custom screeners:

• Video: Find coins with recent trend upgrade
• Video: Fresh bullish MACD crossover (trend and momentum trading strategy)
• Video: Fresh bullish MACD crossover with RSI confirmation (trend and momentum trading strategy
• Video: Early detection of momentum inflection using MACD Histogram indicator
• Video: Buy/Sell signal based on Bullish/Bearish MACD crossovers for a specific coin (example: Cardano (ADA))
• Video: Moving average crossovers (example: EMA 12 / 50 bullish crossovers)
• Video: Using ATH (all-time-high) indicator (6 different filters)
• Video: Oversold coins in a Long-Term Uptrend