  Large fermionic multiplets appear in different extensions of the Standard
Model (SM), which are essential to predict small neutrino masses, relic
abundance of the dark matter (DM) and the measured value of muon anomalous
magnetic moment (muon (g-2)). Models containing quintuplet of fermions
($\Sigma$), along with other scalar multiplets, can address recent anomalies in
the flavor sector while satisfying the constraints from the electroweak
physics. In standard scenarios, the exotic fermions couple with the SM
particles directly and there exists a strong limit on their masses from
collider experiments such as the Large Hadron Collider (LHC). In this paper, we
choose a particular scenario where the quintuplet fermions are heavier than the
scalars, which is naturally motivated from the muon (g-2) data. A unique nature
of these models is that they predict non-standard signatures at the colliders
as the quintuplet fermions decay via the scalars once produced at the
colliders. We study these non-standard interactions and provide alternative
search strategies for these exotic fermions at the LHC and future linear
colliders (such as $e^+e^-$ colliders). We also discuss their exclusion and
discovery limits. For the doubly charged quintuplet fermion
($\Sigma^{\pm\pm}$), discovery is possible with 5$\sigma$ significance at
integrated luminosity of 3000 fb$^{-1}$ at 14 TeV LHC if $M_\Sigma\leq 980$
GeV. For the singly charged quintuplet fermion ($\Sigma^\pm$), the discovery is
challenging at LHC but there might be a possibility of 5 $\sigma$ discovery
with 1000 fb$^{-1}$ luminosity at $e^+e^-$ collider for $M_\Sigma\leq 700$ GeV.
