If I ran a dictatorship wanted to create as much destruction as possible I would send out a few different viruses out into a city. Locking off the city from the rest of the country but not to the world. During this time I would ask for stock up on the world's supply of PPE, masks etc. via asking for donations or getting people in other countries to buy it off the shelves and send it through.
These are the viruses I would let out into a city:
I would create one that is a pneumonia similar SARS but make it less dangerous. I will call this virus SARS-Lite.
I would create one that presents similar to SARS, that is actually a microthrombi issue causing oxygen levels to dip and organs to fail due to damaged blood vessels. I will call this virus Happy Hypoxemia.
I would create one that has the same flu-like symptoms at the beginning of the other two but after a few months of having the virus, it is basically the same as a chemical attack with 100% mortality. I will call this virus Xi Virus.
I would hide the outbreak for a few months, then I would admit there is a virus but it is nothing to worry about. I would send a few people from Wuhan to overseas countries infect them with the less dangerous version of SARS and get them to present to hospital in their respective countries. This would help demonstrate that it isn't anything to really worry about.
Here are some links to the first cases overseas:
https://www.nejm.org/doi/full/10.1056/NEJMoa2001191
https://www.health.gov.au/ministers/the-hon-greg-hunt-mp/media/first-confirmed-case-of-novel-coronavirus-in-australia
I would share the genome with the world (for SARS-lite), so they think that this is the virus we need to create the vaccine for. (The genome for SARS, MERS etc were never shared with the western world)
I would tell other countries that they need to invest in ventilators as this is the only treatment that works. Where really the only people that need them are a really small percentage of people that catch SARS-Lite need them and it kills the people with the Happy Hypoxemia virus. Making countries waste time and money, plus lose lives.
I would make it so if you contracted the Xi virus you wouldn't even test positive for COVID-19, and I would design the virus's destruction to be impossible to pick up on a blood test or scan. There would be many people out there with a deadly virus that isn't even counted in each country tally. These people would start dropping dead as countries re-open. I would disguise this as a second wave.
The people with the Xi virus would be overlooked, as they don't test positive and their symptoms don't escalate until they drop dead in the streets. They would get told 80 days after infection that it's all just anxiety or post-viral fatigue.
I would keep people focused on working toward a vaccine and not a treatment. The vaccine that would only work for the SARS-Lite virus, not the other two viruses making it a pointless endeavour. People will believe they are immune after they are infected or once they have had the vaccine, but they are wrong.
Remember this nurse?
https://www.invidio.us/watch?v=0TfVDgzSE88&feature=youtu.be
Here are some videos to help refresh your memory of what happened in Wuhan:
https://archive.nothingburger.today/Videos/Infected_or_Dead/