I don't grow many chillies, but always have one or two plants every year, milder varieties like Early Green Jalapeno, Fish Peppers, Wax Peppers, etc...I've never had any issue just putting the seed straight into the media 0.5cm deep (usually John Innes soil or wormcasts) and germinating in plastic cups on the windowsill, with a wee bit of cling-film loosely draped over the top just to stop the top of the soil drying out as fast. I
pretty sure I've always had 100% germination using seeds that are 1-4 years old
. I actually get worse germinataion rates with my older tomato seeds lol, but the chillis do germinate more slowly.
I have a friend who likes to grow the super-hot varites like Komodo Dragon, Dragon's Breath and Moruga Scorpion - he seemed top have issues with the germination rate of these and went to the length of trying to get fresh chillis from the shops to remove seeds. I'd always check if my local Tescos had any of the super-hot chillis in stock lol (they sell out very fast!).
Makes me wonder if I've just been lucky with my seed sources, or if some chilli varieties are much harder to germinate?
Edit to add: I do sometimes spray seaweed extract om the surface of the soil of any seeds I'm waiting to germinate if I'm feeding any of my other plants at the same time, but I doubt this would make much difference and don't always do it.