When I tried Fritzing for the first time today, I unfortunately had to notice that two parts are missing. A NodeMCU has already created and released squix78, thanks for that. But unfortunately I could not find a RS232-TTL converter (MAX3232). No problem, then I just create an own part. With this manual this is relatively easy. Unfortunately the part editor did not accept the SVG's I created with Adobe Illustrator. After a long time of trying I found out that the following export settings are necessary. Important is the number of decimal places:
The final part:
You could download my MAX3232 RS232-to-TTL-Converter Breakout Board here. To use it, drag and drop it into you sketch.