Can the CRM be linked to invoicing and e-invoicing?

Yes, for the invoice itself, and it is one of the integrations with the clearest time saving. The link removes manual re-keying of customer data between sales and invoicing. What it does not do is file invoices with a state system: that is a separate step, regulated nationally.

Short answer

From the numbered quote of a won deal you can create the invoice draft, with the customer data already filled in.
4softcrm and 4invoices do not transmit invoices to a national e-invoicing system; if your country requires that, it is a separate, regulated step.
Check the rules that apply in Ireland on e-invoicing and invoice content before you automate any step; some customers, public bodies in particular, may require a specific electronic format.
The link is made through 4invoices from the 4b2b ecosystem; for other invoicing software you use the API or webhooks.
Always verify that the VAT number and address in the CRM are correct, otherwise the invoice has to be corrected afterwards.

The flow, from deal to invoice

The rep marks the deal as won and the accepted quote is attached.
The customer’s billing data (name, VAT number, address) is carried into the invoice draft.
The invoice draft is created in 4invoices from the numbered quote, with the “Issue invoice” button.
If your country requires e-invoicing or reporting to a state system, that step is handled separately, according to your national rules.
Check the payment status in the invoicing software before the rep asks for a new order.

What to check before enabling the integration

That the billing data in the CRM is validated — a wrong VAT number means a corrected invoice later.
Who is allowed to issue the invoice: not every sales rep should be able to, and a deal marked won twice must not produce two invoices.
What happens with credit notes and partial invoices — the flow must cover the negative cases too.
Whether your national rules require e-invoicing or reporting for your customers, and who owns that step.

Common mistakes

Keeping billing data only in the invoicing software while the CRM holds trade names — they never match.
Automating issuance with no human validation for large orders.
Assuming the CRM-to-invoicing link also files invoices with a state system. It does not, so that step needs its own owner.

How 4softcrm helps

A link to 4invoices: from the numbered quote you create the invoice draft with the “Issue invoice” button, with no third-party connectors.
API and webhooks if you use different invoicing software or your own ERP.
Separate permissions for issuing documents, distinct from pipeline access.