Wireguard as an alternative to bridge-adapter for Virtualbox?

[doremifajb]

Hello! I have OpenWRT 22.03.3 on EdgeRouterX, and my laptop is Macbook Pro mid 2012. I have Win 8.1 on Virtualbox. Usually, the network connection on Win 8.1 is over "NAT adapter".
I have two devices for which management softwares are available only on windows. One of them (an audio equipment) really required it to be on Bridge-Adapter, and I had been able to set Virtualbox up for it, though it was pretty messy each time, and each time different settings. It looks like it's not guaranteed to work. Now, it won't do it anymore. Bridge mode doesn't work. (Supposedly it should still work if I'm using ethernet port, but mine is physically broken, so I use USB adapter, and that doesn't seem to work.)

In a desperate effort, I set up Wireguard peer on Win8.1, but it still cannot communicate with the device as I need.

The software is seeing it, if I enter the address for "Static route" or "Proxy" on that software (whatever it means). But it can see devices, which it cannot synchronize with. I can also ping the device from win cmd terminal.
I tried to put on OpenWRT redirecting:

config redirect
	option dest 'lan'
	option target 'DNAT'
	option name 'blu50 to wireguard'
	list proto 'all'
	option src 'lan'
	option src_ip '192.168.1.111'
	option dest_ip '192.168.9.3'

But it didn't help....
9.3 is the IP address of VPN interface. The address of the peer is 9.2.

I would appreciate very much if someone could help me with this. Or, in case I'm hitting at a totally wrong direction, please let me know.

If it doesn't work, I will look for someone who would let me use her win, so it's not that bad, but it would be nice, if I can use my own for this device.

[doremifajb]

In the end, I made it work..... it's not clear if everything what I did was necessary, but that's what I did:

In the redirect, I put

option dest_ip '192.168.9.2'

(the address of win8.1) instead of 9.3 (vpn interface).
On Wireguard on win8.1, I used to have the address 192.168.9.2/32, I changed it to 192.168.9.2/16.
Then it came out

and the management software (it's called audioArtitect) was able to synchronize itself with the device.

Since I solved it on my own, I thought about deleting my posting, but in case someone else might experience a similar problem, I'm going to leave it here. And I will also appreciate your comments (e.g. a better way, something being superfluous/dangerous).