@Zehua Zhou
I've looked into this situation quite a bit before. From my perspective, the main issue I encountered is whether you're allowed to transfer ownership from your personal name to an LLC. Typically, loan documents prohibit transferring ownership.
If you transfer ownership to an LLC, you'll typically need to switch the insurance to the LLC's name. When you do this, your bank will often be notified of the change in the insurancer's name. While this rarely happens, it allows the banks the opportunity to call your loan, claiming you've breached the terms of the loan agreement. This means they could require you to repay the entire loan balance.
People involved in the loan business will often say this situation never happens. However, given the recent rise in interest rates, if you're locked in at a 3% rate and the market is now at 7.5%, there's a possibility that the bank might call your loan if you've violated the loan covenants. Many people believe this won't happen, but it's a risk that exists. So, it's something you need to be aware of and consider.
If your goal in moving the property to an LLC is to protect yourself, it might be simpler to buy an umbrella policy to cover yourself against any issues. This can be beneficial for both your real estate investing and your personal life. So it's like killing two birds with one stone.