Record-a-trade-via-broker-to-sell-in-WL-later

No it doesn’t work that way. The strategy in WL will always run on a theoretical basis so it will still issue the sell signal for the position that you manually entered with the broker.

QUOTE:
[WealthLab] will still issue the sell signal for the position that you manually entered with the broker.

Just to be clear, your broker needs to be "compatible" with WealthLab and you need to have that particular broker extension installed into WealthLab so WealthLab knows which stocks your broker account carries.

But you don't need WealthLab to be connected to your compatible broker when you make your manual trade on the broker side.

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If you are saying your broker is not currently compatible with WealthLab and you want a "custom" broker extension developed specifically for it, that's a separate issue. It would probably be easiest (and cheapest) to switch to a different broker that WealthLab already has an extension for.