I run both types of plugs on engines with points but only non resistor plugs with magnetos and you run a relatively soft plug for a Scott. If you find it not running totally clean go a grade softer but always check plug colours before. There are so many variations (14mm, 18mm, long reach, short reach) of head I cannot recommend a plug without knowing that info but once that is established you are down to just a couple of choices.
I personally use Champions as I always have found them more consistent than NGK’s (manufacturing quality wise) and for serious beans a 6 to 8, general fast riding an 8 or 9, and town and slow riding a 10 or 11 grade. I’ve run as hard as a 4 but you need a spot on mixture and to ride it flat out to get it to run clean and hard plugs are generally more difficult to get the bike started. Note the numbers are for the general N range and do not directly translate to the L82/L86/D14/D16 etc
Technicalities seection 5.4 covers the subject too.
Let us know what thread and reach your head has and I’m sure you’ll get a few recommendations.
I note the very first post mentions using plugs from a car. Of course Minis used N9 plugs (now N9YC or N9YCC) for long reach 14mm which work very well in a Scott too! About the right plug for general riding if they fit your head.
Further to the discussions about moving the plug further into the chamber this of course is easliy acheived by using a projected tip plug which most soft plugs tend to be.
Hope that helps,