The 46-year-old from Abergavenny, whose previous victory on the Ladies Tour came in India in 2018, was tied for seventh on one under.
Morgan is two shots off the lead held by England duo Charlotte Thompson and Gabrielle Cowley and Lucie Malchirand of France.
Wales’ Lydia Hall and Amy Boulden were three shots further back on +2 after the opening round at Golf Du Medoc.
St Asaph star Boulden teed off having claimed her maiden LET title in Switzerland last weekend.
Boulden’s victory took her to fifth on the Race To Costa Del Sol standings.