Welcome to the Community,
I'm not aware of a way to directly convert an Acronis (.tib) file to a virtual disk (.vmdk).
What you may do is to create a new virtual machine, boot it from the Acronis recovery image, and restore the backup (.tib) this way.
To access the .tib file from the VM, you may e.g. pass through an USB device, or place the .tib file on a network share.
André