yes, there is trick/hack to use 2nd one, but it request FA override by Custom CSS.
I guess, you don't need VK for obvious reasons.
what is "fa-beat" ???
In FA 5 Free, I could find only <i class="fas fa-heartbeat"></i> with unicode f21e. So let imagine that is what you need:
- In VK Username you put needed URL with https
- Then using tab Custom Code > Custom CSS you put that
.fa-vk::before {
content: "\f21e";
font-family: "Font Awesome 5 Free";
font-weight: bold;
}
to get

so simple, you don't have to be McGyver ;)