History is full of people adopting and abandoning crops, which rewild back to its natural state.
You might want to ask in r/ecology for more detailed answers, as well as contact the Department of Commerce ask about all the list of banned plants and seeds for import to the USA and why. https://www.cbp.gov/travel/clearing-cbp/bringing-agricultural-products-united-states
I would say, yes there are many examples. Dandelions? Introduced as garden herbs for salads and tea. Crabgrass? This is actually a very productive grain plant per size; you hand-harvest and then grind into flour. it was imported by Polish and other settlers as a food source. Now it's a lawn nuisance.

The one thing about crop plants intended for human consumption is that they usually have larger seeds (humans prefer these) and tend to thrive in quality soil, so they don't necessarily compete with native plants that well.

However, forage plants for livestock, or even tree crops, are a different story. You want plants that do well in marginal soils, can handle erosion, and are very vigorous and are good grazing.

When it comes to importing plants to use as forage for livestock, the consequences can be a little stronger because of all the land we use for pasture adjoining vulnerable ecosystems. We have buffelgrass, which is native to Africa, Europe, and Asia, (Pennisetum ciliare species).

It was introduced into Texas in the 1940s to stabilize overgrazed lands and provide forage. It is considered highly invasive. In the US it's spreading in SW deserts and disturbing native species. Worse yet, it's flammable, so it increases the risk of fire. And fire itself helps it spread over native desert plants as it's well adapted to fire ecology, being a pioneer species (i.e an early colonizing species in disturbed habit.)

To quote from this below link: " Buffelgrass fine fuel loads are generally much higher than fine fuel loads from native plants in desert environments. Thus, fires in buffelgrass stands may have longer flame lengths, greater rates of spread, and higher temperatures than fires in native desert vegetation, and cause high mortality in native flora and fauna [43].

Buffelgrass stands burn "very hot" [24] and can burn when green [42,129]. In the Sonoran Desert, buffelgrass-fueled fires can reach temperatures so hot that the soil is scorched and the bedrock cracked [42]. Headfires in buffelgrass stands can reach temperatures of 1,090 to 1,300 °F (585-700 °C) [27,103]. Esque and others [42] state that buffelgrass grows into an "almost-woody subshrub", accumulating flammable material over several years, "in effect unlinking fire frequency from annual climatic variability and increasing the fire intensity"."

https://www.fs.fed.us/database/feis/plants/graminoid/pencil/all.html

But that's not a historical example. It's a disaster happening right now.