I also moved overseas last year / early this year and had to get rid of / leave behind some stuff. Actually, an entire household worth of (leftover) stuff (furniture, appliances, clothes, cleaning and other misc supplies, plants, decor, and etc.) and not just electronics, since this was my parents' house. I ended up throwing out almost nothing, though... well, mostly empty boxes that I picked up for free from the neighborhood (or recycling days) to pack my stuff I wanted to keep/move, and some scrap building materials I had accumulated over the years (wood, drywall, pipes and fittings of various types and sizes, and etc.)
The key is to take your time and not try to do it all at once. Space it out over time. Yet at the same time, try to list as much as you can (without taking too much time away from your normal life activities) that you know you won't need or feel comfortable parting with.
Sometimes, items may sit for a while with no one interested in them, because the demand for used stuff can be sporadic and a bit unpredictable. This is especially true for retro hardware. And sometimes things will get snapped away the instant you list them. Price is not really relevant. I've had stuff listed for FREE or nearly so that I thought were nice / usable, and they sat for weeks in front of my porch/door for pickup before anyone came to take them. I've also had the complete opposite too: items that I thought were not that useful or great, yet people lining at my door saying "here, take my money NOW!" 🤣
As for bulk sale vs. individial sales... yes, bulk will get rid of stuff faster, but it may take longer before "the right" person shows up.
Perhaps it may be best to make a few bulk list ads now and then eventually make ads/posts for individual items as you go along - i.e. make a general bulk post on whatever platform is popular in your country area, and then as time allows, make individual posts (preferably with pictures) of the stuff you have for sale / to give away.
Also, beware that if you live in a place that is far off from a big city or people need to drive far (or have your stuff shipped far away), that is often the biggest limiting factor as to who is willing to take/buy the stuff.
In short: if Portal guns were a real thing, you could probably clear out your house in a day or quicker without having to lift a finger. 🤣 Sadly, we are not there yet (and probably won't ever be... but let's not stop dreaming 😀 )
That said, I won't lie and say that my move went without a hitch. Actually, quite the opposite. There were a number of stuff that I left behind or sold that I wish I would have kept now. And likewise, there were some stuff that I really wish I didn't take (mostly stuff that my parents asked me explicitly to take, yet had no interest in them once I brought them over.) But it is what it is. I'll know better for next time, if there is one. :p: If not, at least I hope sharing my experience / advice here can be of some use to you.