Can you use it on 19mm grooves as well?
Yes most definitely silicone flows to fill the response groove so it works on any meter groove…
You’re asking two questions, one regarding “any” yoyo and one regarding 19 mm grooves. The answer to the first one is “it depends”. Mainly on the depth of the groove as noted by kadabrium. The answer to the second is yes.
Take a look at any yyf sized pad well, now look at the yoyo you want to silicone. If they are similar depth then you’re good. If, however, it seems like it was built to house nothing thicker than a piece of paper then stick with whatever it came stock with as a replacement. If the yoyo was made in the last five years then you’re probably good unless its a looper.